PCS TR 002 Waste to Energy (Thermal Recovery)_v1.0

Document Control

Document identification

• Document code: PCS-TR-002

• Title: Waste-to-Energy (Thermal Recovery)

• Scope: Thermal treatment of eligible waste streams with measurable energy recovery (electricity and/or heat/steam and/or syngas-to-energy pathways), including mass-burn incineration, advanced thermal treatment (gasification/pyrolysis where outputs are combusted for energy), and RDF/SRF co-firing, subject to applicability conditions.

• Crediting outcome: Emission reductions (tCO₂e) from avoided baseline waste-disposal emissions (including methane where applicable) and/or displacement of fossil energy, net of project emissions and leakage, consistent with PCS conservativeness rules.

Version history and change log

Table DC-1. Revision history

Version	Date	Status	Summary of changes	Prepared by	Approved by
v1.0	TBD	Draft	Initial release for review	PCS Secretariat	TBD

Superseded versions

No superseded versions for v1.0.

Governance note on versioning and archiving

Only the latest approved version of this methodology shall be used for new project registrations. Superseded versions shall be archived and retained for traceability and audit purposes, including for projects registered under earlier versions where applicable, consistent with PCS governance rules.

Chapter 1 - Introduction And Scope

1.1 Purpose

PCS-TR-002 establishes the methodological, scientific, and operational requirements for quantifying greenhouse gas (GHG) emission reductions from Waste-to-Energy (WtE) thermal recovery systems. These systems thermally convert waste into useful energy—typically electricity, heat, steam, or syngas—while simultaneously preventing methane-generation pathways associated with uncontrolled land disposal.

The primary purpose of this technical requirement is to ensure that emission reductions attributed to WtE projects are real, measurable, and scientifically justified. PCS-TR-002 provides a structured approach for defining baselines, project emissions, monitoring systems, and calculation methods. It aligns with international best practice, including the IPCC 2006/2019 Guidelines, UNFCCC methodological frameworks, the EU Industrial Emissions Directive, ISO life-cycle principles, and additional scientific literature. Where uncertainties arise, the methodology adopts conservative assumptions to avoid over-crediting and maintain environmental integrity.

1.2 Scope of Technologies Covered

PCS-TR-002 covers all major classes of thermal waste management technologies used globally. Mass-burn incineration systems such as moving grate furnaces, fluidized bed combustors, and rotary kilns are included, as they oxidize waste under excess-air conditions and recover thermal energy through steam cycles or organic Rankine systems. Advanced thermal treatment technologies such as gasification and pyrolysis fall within scope provided that the syngas or pyrolytic products are ultimately combusted or used in an energy recovery pathway.

The methodology also applies to waste-derived fuels used in industrial combustion systems. Refuse-derived fuel (RDF) and solid recovered fuel (SRF) may be co-fired in cement kilns, industrial boilers, or power plants. In such applications, the emission reduction arises from the displacement of fossil fuels by the biogenic component of the waste-derived fuel.

Across all technology categories, PCS adopts a biogenic-only crediting framework. Biogenic carbon is treated as climate-neutral in accordance with IPCC rules, while fossil-derived waste fractions (e.g., plastics, synthetic textiles, rubber) are treated as carbon-positive and must be fully accounted for in project emissions. No credit is awarded for combusting fossil waste materials under any circumstances.

1.3 Scope of Feedstocks

The methodology applies to non-hazardous solid waste streams suitable for controlled thermal treatment. These include municipal solid waste, commercial and industrial wastes, agricultural residues, sewage sludge (when co-fired or thermally treated with MSW), and processed waste fuels such as RDF or SRF.

Feedstocks that introduce environmental or methodological risks fall outside the scope of PCS-TR-002. These include hazardous and medical wastes, chemically contaminated industrial residues, electronic waste, or any material prohibited under national regulations. Projects must demonstrate that feedstocks are sourced from permitted waste management systems and that their composition remains sufficiently stable to support accurate emissions accounting.

1.4 Emissions and Reductions Within Scope

PCS-TR-002 accounts for all material GHG flows affected by the project. Emission reductions arise primarily from two mechanisms: the avoidance of methane generation at baseline disposal sites and the displacement of fossil-based electricity or thermal energy. These benefits are partially offset by project emissions, which include fossil CO₂ released from the combustion of non-biogenic waste fractions, nitrous oxide and methane slip from thermal processes, auxiliary fossil fuel consumption, electricity used in plant operations, residue handling emissions, and upstream or downstream emissions directly attributable to project activity.

Biogenic CO₂ emissions from combustion are treated as carbon-neutral following IPCC conventions and do not enter the emission reduction equation. Emissions indirectly related to facility construction or equipment manufacturing are excluded unless they materially influence project outcomes, in which case they must be documented and justified at validation.

1.5 Alignment With Scientific and Regulatory Standards

The technical foundation of PCS-TR-002 is drawn from internationally recognized references. The IPCC Guidelines provide the basis for biogenic carbon accounting, fossil CO₂ quantification, and waste sector characterization. The methodology also incorporates principles from the UNFCCC CDM waste incineration and fuel-switching methodologies, ensuring that baseline and project scenarios reflect scientifically validated pathways.

Relevant regulatory documents inform the environmental safeguards and performance thresholds. These include the EU Best Available Techniques (BAT) Reference Document for Waste Incineration, the US EPA AP-42 emissions factors, and ISO 14040-series life-cycle assessment principles. Where discrepancies exist across sources, PCS adopts the more conservative interpretation to minimize uncertainty and avoid overestimation of emission reductions.

1.6 Project Duration and Crediting Framework

Projects may apply for a crediting period of up to ten years, renewable upon demonstration that project conditions remain stable and that performance does not deteriorate. The crediting period may be terminated early if the facility violates environmental compliance conditions, if the waste composition materially shifts toward fossil-dominated streams, or if the energy recovery efficiency drops below the minimum thresholds established in PCS-TR-002.

Crediting is strictly tied to measurable methane avoidance and fossil fuel displacement. If energy recovery ceases for any reason, crediting must pause until the project resumes full compliance.

1.7 Co-Benefits Outside the Crediting Boundary

While not included in emission reduction calculations, WtE projects frequently deliver additional environmental and social benefits. These may include reductions in open burning, improved public health conditions, enhanced waste management infrastructure, recovery of recyclable metals, and the production of ash aggregates suitable for construction applications. PCS requires these co-benefits to be documented for transparency but does not monetize them to avoid double-counting or overlap with other sustainability frameworks.

1.8 Overarching Conservativeness Principle

A central requirement of PCS-TR-002 is the application of conservative assumptions whenever uncertainty exists. Waste composition must be characterized rigorously, and where data gaps persist, fossil fractions are assumed rather than ignored. Energy displacement benefits rely on defensible benchmarks rather than optimistic grid or fuel emission factors. Thermal efficiencies must be demonstrated through monitoring rather than assumed through design specifications.

This conservativeness standard ensures that all credited emission reductions represent real, measurable climate benefits consistent with PCS integrity requirements.

Chapter 2 - Applicability Conditions

2.1 Purpose of Applicability Conditions

Applicability conditions ensure that PCS-TR-002 is used only for projects that can generate scientifically credible and environmentally robust emission reductions. Waste-to-Energy (WtE) systems vary widely in design, feedstock composition, combustion characteristics, emission profiles, and energy recovery performance. This chapter defines the boundaries within which the methodology may be validly applied and establishes conditions that prevent misapplication, over-crediting, or inappropriate technology deployment.

The conditions also ensure alignment with IPCC classification of waste combustion, EU waste incineration benchmarks, and internationally accepted thermal treatment performance standards.

2.2 Eligible Project Types

The methodology is applicable to facilities that thermally treat waste in controlled, regulated systems and recover usable energy. Eligible systems include:

• Mass-burn incineration operating under excess-air conditions and equipped with reliable combustion control, continuous emission monitoring where required, and a functional energy recovery unit.

• Advanced thermal treatment systems, such as gasifiers and pyrolysis reactors, provided that the syngas, pyrolysis gas, or vaporized bio-oil is combusted in a controlled system to produce electricity, heat, or steam.

• Co-firing of waste-derived fuels, such as RDF and SRF, in industrial combustion equipment—including cement kilns, power plants, and industrial boilers—where the energy output displaces fossil fuel consumption.

Across all systems, the project must demonstrate measurable thermal or electrical energy recovery. WtE facilities that combust waste without recovering energy fall outside the scope of this methodology.

2.3 Eligible Feedstocks and Composition Requirements

Only non-hazardous waste streams suitable for controlled thermal treatment are eligible. Eligible feedstocks include municipal solid waste, commercial and industrial wastes, pre-processed RDF/SRF, agricultural residues, and sewage sludge when co-processed with solid waste. Feedstocks must comply with national regulatory classifications and must not include materials requiring specialized hazardous-waste incineration technologies.

The methodology requires an understanding of waste composition, particularly the biogenic versus fossil-derived carbon fractions. This distinction is essential for quantifying fossil CO₂ emissions and biogenic displacement benefits. Facilities must demonstrate that feedstock composition falls within a stable and predictable range. If composition varies substantially or lacks reliable characterization, conservative assumptions must be applied, with fossil fractions given priority in the absence of data.

2.4 Regulatory and Environmental Compliance

The project must operate in full compliance with environmental regulations applicable in the host country, including air emission limits, ash handling protocols, and waste acceptance criteria. Compliance with regulatory requirements is fundamental to the applicability of the methodology because thermal treatment technologies can produce significant pollutants if improperly operated.

Projects under investigation for environmental violations or with unresolved non-compliance findings are not eligible until the issues are remedied. Continuous or periodic monitoring requirements set by national authorities, such as stack emission measurements for CO₂, NOₓ, SO₂, PM, and heavy metals, must be maintained throughout the crediting period.

Where national regulations do not exist or are weaker than international norms, the project must meet equivalent performance benchmarks sourced from internationally recognized frameworks such as the EU Industrial Emissions Directive or relevant BAT (Best Available Techniques) reference documents.

2.5 Minimum Energy Recovery Performance

To ensure genuine displacement of fossil energy, WtE systems must meet minimum energy recovery efficiency thresholds. These thresholds prevent crediting from facilities that primarily destroy waste but do not meaningfully contribute to energy substitution.

For mass-burn incineration, the facility must demonstrate sustained thermal efficiency consistent with the lower range of internationally accepted performance metrics for energy recovery incinerators. For gasification and pyrolysis systems, crediting applies only if the syngas or pyrolytic products are combusted in boilers, engines, turbines, or equivalent systems. Facilities that flare syngas without recovering energy are ineligible.

Co-firing systems must document the fossil fuel that is displaced, the net heat contribution of the waste-derived fuel, and the proportion of biogenic carbon in the displaced energy stream. Projects unable to reliably quantify displacement factors cannot apply this methodology.

2.6 Additionality and Project Start Date Conditions

The project must demonstrate additionality by showing that it would not have occurred in the absence of carbon finance or equivalent incentives. This includes demonstrating that the installation of WtE infrastructure represents an investment beyond routine waste disposal obligations and that local regulations do not already mandate the installation or operation of such systems.

The start date must align with PCS rules, and crediting may only occur after the project is validated. Activities initiated before validation must provide verifiable evidence of intent to seek carbon finance.

2.7 Boundary and Technology Conditions

The project boundary must encompass all emission sources materially affected by the intervention. This includes waste supply chains, thermal treatment units, flue gas cleaning systems, energy recovery systems, residue handling units, and all auxiliary energy inputs.

Technologies that do not operate under stable process control, such as open burning, uncontrolled combustion pits, or ad-hoc thermal systems lacking engineered combustion chambers, are excluded. The methodology applies only to engineered systems with defined combustion parameters, predictable energy flows, and verifiable emission profiles.

2.8 Exclusions and Ineligible Conditions

The methodology may not be applied to facilities whose primary purpose is hazardous waste destruction, medical waste treatment, or chemical incineration. Similarly, facilities using waste streams with high fossil content and negligible biogenic proportion may be ineligible if they cannot demonstrate meaningful fossil fuel displacement or methane avoidance benefits.

Projects that cannot quantify fossil CO₂ emissions due to insufficient waste characterization are excluded. Systems with persistent operational instability—characterized by repeated shutdowns, temperature excursions, or uncontrolled emissions—cannot be credited until compliance is restored and performance stabilized.

2.9 Conservativeness in Applicability

Uncertainty in applicability conditions requires conservative decisions. Where inclusion or exclusion is ambiguous, PCS mandates defaulting toward non-crediting unless clear evidence demonstrates full compliance. This ensures methodological integrity and prevents crediting from systems that may deliver uncertain or overstated climate benefits.

Chapter 3 - Project Boundary

3.1 Purpose of the Project Boundary

The project boundary defines all physical locations, systems, processes, emission sources, and energy flows that must be considered when quantifying emission reductions. A precise boundary ensures that all material greenhouse gas (GHG) impacts—both beneficial and adverse—are transparently captured. Unlike simpler waste management interventions, Waste-to-Energy (WtE) systems create multiple interacting flows: combustion gases, auxiliary fuels, generated electricity, thermal outputs, residues, and transport emissions. For this reason, the boundary for PCS-TR-002 must be comprehensive, scientifically defensible, and consistent with IPCC waste and energy sector guidance.

3.2 Physical and Spatial Boundary

The physical boundary encompasses the WtE facility and all upstream and downstream processes directly affected by the project. It includes the waste reception and storage zones, feed preparation or RDF/SRF processing areas, combustion chambers or thermal reactors, boilers or energy recovery units, air-pollution control systems, flue gas stacks, ash or residue handling systems, internal transport networks, and onsite utilities.

For co-firing systems, the spatial boundary includes the industrial combustion unit where the waste-derived fuel displaces fossil fuels, as well as any pre-processing sites responsible for producing the RDF or SRF used in the project. If energy is exported, the boundary extends to the point of grid or heat-network interconnection but does not include the receiving grid or district heating infrastructure.

3.3 Greenhouse Gas Boundary

All GHG flows materially influenced by the project must be included. These flows are categorized into baseline emissions, project emissions, and emission reductions.

• Baseline Emission Sources: Baseline emissions originate from the waste management pathway that would have occurred in the absence of the project. This typically involves methane generation from land disposal, open dumping, or other unmanaged decay pathways. For co-firing systems, the baseline reflects the fossil fuel that would have been used had the waste-derived fuel not been available.

• Project Emission Sources: Project emissions consist of fossil CO₂ released from the combustion of non-biogenic waste fractions, methane and nitrous oxide emissions from thermal units, auxiliary fossil fuel consumption, electricity use for plant operation, residue treatment impacts, and transport emissions. Air-pollution control systems may introduce additional energy requirements that must also be accounted for.

• Emission Reduction Sources: Emission reductions derive from two mechanisms: avoided methane emissions resulting from the diversion of biogenic waste away from landfills or dumps, and displacement of fossil fuels in energy systems using the electricity, heat, or steam produced from biogenic waste fractions.

3.4 Temporal Boundary

The temporal boundary begins at the start of facility commissioning or at the point when the system begins generating measurable energy recovery, whichever is later. The boundary continues throughout the crediting period, provided the facility operates in compliance with environmental and operational requirements. Any periods of abnormal operation—such as extended shutdowns, reduced combustion efficiency, or failure of pollution control systems—must be documented and excluded from crediting when they affect project performance or emission accuracy.

Waste deposition histories extending back decades may be relevant when the baseline scenario involves landfill methane avoidance. Historical waste data outside the project period remain part of the baseline boundary if they influence ongoing methane decay dynamics.

3.5 Upstream and Downstream Processes

Upstream processes include the collection and transport of waste to the facility, the energy and materials involved in RDF/SRF preparation, and any preprocessing steps necessary for advanced thermal treatment technologies. Only processes that change as a result of the WtE project are included; routine waste collection not influenced by project activity is excluded unless the project demonstrably alters its emissions.

Downstream processes include the handling, stabilization, or beneficial use of bottom ash, fly ash, or other thermal residues. If residues displace construction materials, the displacement effect may be documented but is not credited under PCS-TR-002 to avoid methodological overlap with material substitution methodologies. Transport and disposal of residues in landfills remain within the project boundary if project activity directly determines their characteristics.

3.6 Energy Boundary

Energy boundaries define how generated energy interacts with fossil fuel displacement. All electricity exported to the grid or used onsite is included within the project boundary. Thermal energy supplied to industrial users or district heating systems is also included. The emission factor for displaced fossil fuel or grid electricity must be consistent with national baselines or PCS default values, whichever are more conservative.

For co-firing systems, the boundary includes the combustion zone where RDF/SRF replaces coal, oil, gas, or petcoke. Only the biogenic fraction of the waste-derived fuel contributes to emission reductions; fossil-derived fractions are treated as additional sources of CO₂.

3.7 Residues and Air-Pollution Control Systems

Residue streams such as bottom ash, boiler ash, fly ash, activated carbon, and spent reagents from flue-gas treatment fall within the boundary. Their handling, transport, and final disposal may generate GHG emissions. Air-pollution control systems—including scrubbers, baghouses, electrostatic precipitators, and catalytic reactors—consume electricity or reagents whose production and use must be accounted for if material.

The presence of pollution control does not reduce project emissions but ensures compliance with environmental regulations—a prerequisite for project eligibility.

3.8 Boundary for Co-Firing Systems

In co-firing applications, the project boundary encompasses the industrial combustion system where fossil fuel displacement occurs. The baseline fuel pathway, its energy content, and its emission factor become defining elements of the boundary. If RDF/SRF is produced offsite, the pre-processing steps also enter the boundary but only to the extent that they change relative to the baseline waste handling system. The boundary does not extend to the entire industrial facility unless project activity measurably affects it.

3.9 Treatment of Biogenic and Fossil Carbon

The boundary explicitly differentiates between biogenic and fossil carbon. Biogenic carbon flows are treated as carbon-neutral following IPCC conventions, while fossil carbon is fully included in project emissions. This differentiation is essential for accurate calculation of displacement benefits and combustion emissions. The boundary must therefore include data systems capable of tracking waste composition, calorific value, and fossil fraction with adequate precision.

3.10 Summary Interpretation of the Boundary

The project boundary incorporates the complete engineered WtE system and all GHG flows that change because of project activity. It excludes indirect, speculative, or unquantifiable impacts but captures all material and conservative sources of emissions. By defining the boundary in this structured manner, PCS-TR-002 ensures transparency, reproducibility, and scientific defensibility across projects, enabling consistent verification and preventing methodological loopholes.

Chapter 4 - Baseline Scenario

4.1 Purpose of the Baseline Scenario

The baseline scenario represents the waste management and energy system conditions that would occur in the absence of the project. It establishes the reference level of greenhouse gas (GHG) emissions against which project performance is measured. Because Waste-to-Energy (WtE) interventions affect both waste disposal pathways and fossil fuel consumption patterns, the baseline must reflect the most plausible and conservative alternative that corresponds to real-world practices in the host region.

A defensible baseline avoids overstating emission reductions and must be grounded in documented waste sector behavior, national energy system characteristics, and scientifically accepted methane-generation models.

4.2 Determining the Most Plausible Baseline Scenario

Several waste management pathways may exist in the absence of the WtE project. The baseline must reflect the option that is most likely to occur, supported by evidence from municipal records, historical waste handling practices, regulatory requirements, and infrastructure availability. In many regions, the default baseline for untreated mixed waste is disposal in an unmanaged or semi-managed landfill. In jurisdictions with more developed systems, waste may be directed to controlled landfills with cover systems or limited flaring.

For co-firing projects, the baseline involves continued use of the fossil fuel that the RDF or SRF would replace. The baseline fossil fuel must be identified based on plant design, historical usage, contractual supply arrangements, and national energy policy. Speculative fuel-switching that is not grounded in historical evidence cannot be used as a baseline.

The selection of the baseline scenario must follow a transparent justification process and must be validated by third-party auditors.

4.3 Baseline Methane Generation and Emissions

The baseline emissions from waste disposal are primarily driven by methane generation resulting from the anaerobic decomposition of the biodegradable fraction of municipal solid waste. The quantity of methane generated in the baseline depends on the waste composition, degradable organic carbon content, climate conditions, degree of waste compaction, and availability of oxygen within disposal sites.

Methane generation in the baseline is estimated using scientifically validated approaches, typically the IPCC First-Order Decay (FOD) model. This model provides a structured method to estimate methane formation over time, especially in settings lacking direct measurement of landfill gas emissions. The baseline methane emission calculation incorporates the methane generated, the fraction released to the atmosphere after oxidation in the landfill cover, and the global warming potential of methane consistent with PCS rules.

4.3.1 Baseline Methane Generation Using the FOD Model

The FOD model expresses methane generation as a function of the mass of waste deposited in past years, the decomposable organic content of the waste, the decay rate constant characteristic of local climate and waste management conditions, the methane correction factor indicating the degree of anaerobic decomposition, and the fraction of decomposed organic carbon converted to methane.

The model distributes methane generation over several years following disposal, yielding a time-dependent decay curve. Parameter values must reflect conservative assumptions informed by national studies, local data, or IPCC defaults. When high-resolution waste composition data exist, they must be used; when data gaps occur, the model must adopt values that prevent overestimation of methane generation.

4.3.2 Baseline Methane Released to the Atmosphere

Not all methane generated is released into the atmosphere because some fraction is oxidized in the upper aerobic layers of landfill cover systems. The quantity of methane emitted is therefore the difference between methane generated and methane oxidized. Unmanaged dumpsites with no cover systems have negligible oxidation, whereas engineered landfills may exhibit limited oxidation depending on cover depth, material type, porosity, moisture, and climatic conditions.

4.3.3 Methane Oxidation in the Baseline

Methane oxidation is a biological process mediated by methanotrophic bacteria. The magnitude of oxidation depends on the presence of oxygen within the cover material. For unmanaged disposal sites, oxidation is typically close to zero. For managed landfills with daily or intermediate cover layers, oxidation may occur at low to moderate levels.

PCS allows the application of oxidation factors only when substantiated by documented cover design or scientific evidence. Oxidation values must not exceed levels suggested in the IPCC Guidelines unless site-specific measurements justify otherwise. When uncertainty exists, conservative assumptions must be used to avoid undervaluing baseline emissions.

4.4 Baseline Scenario for Fossil Fuel Displacement

For WtE projects generating electricity or heat, the baseline scenario must also reflect the fossil fuel that would otherwise have been consumed to produce an equivalent amount of energy. This is relevant for both mass-burn incineration and co-firing applications. In electricity-dominant systems, the baseline is typically the national or regional grid emission factor. In thermal energy systems, the baseline reflects the fossil fuel that the user historically utilized.

The baseline emission factor must be consistent with official national values where available, and must default to conservative PCS benchmarks when multiple values exist or when uncertainty cannot be resolved.

4.5 Exclusions and Clarifications

The baseline must not assume improvements that are unlikely to occur in practice. For example, uncontrolled dump sites should not be assigned methane capture or gas-flaring technologies unless there is a clear commitment and financing mechanism for such upgrades. Similarly, speculative landfill closures or large-scale waste diversion programs should not be incorporated unless supported by credible public plans.

No credit may be awarded for reducing emissions that would not occur under the baseline scenario, nor may the baseline assume future improvements that reduce baseline emissions unless they are legally mandated.

4.6 Summary Interpretation of Baseline Logic

The baseline scenario represents a conservative and evidence-based reference case against which project performance is measured. It incorporates methane formation from waste disposal when relevant, reflects fossil fuel consumption that would otherwise occur, and adheres to scientifically validated modelling principles. Clear delineation of the baseline ensures transparency and prevents the overstatement of emission reductions attributable to Waste-to-Energy interventions.

Chapter 5 - Project Scenario

5.1 Purpose of the Project Scenario

The project scenario describes the conditions that prevail after the Waste-to-Energy (WtE) system is implemented, including all thermal treatment, energy recovery, and operational processes that influence greenhouse gas emissions. It establishes the emission sources and energy outputs attributable to the project, forming the basis for calculating project emissions and resulting emission reductions.

The project scenario must be defined clearly enough for auditors to verify each component, from waste reception to energy export and residue handling. It captures all measurable physical, chemical, and energy transformations resulting from the installation and operation of the WtE system.

5.2 Overview of the Waste-to-Energy System Under the Project

A compliant WtE project under PCS-TR-002 operates an engineered thermal treatment system designed to convert waste into usable energy while controlling emissions. Depending on technology type, thermal conversion may occur through complete oxidation (incineration) or through sub-stoichiometric or oxygen-free processing (gasification and pyrolysis), followed by combustion of produced syngas or vapors.

Across all technology pathways, the defining attribute of the project scenario is the controlled environment in which waste is thermally processed, replacing uncontrolled anaerobic decomposition or fossil fuel use.

The project includes engineered combustion chambers or reactors, boilers or heat-recovery systems, turbines or generators, flue-gas cleaning systems, auxiliary power units, residue handling facilities, and energy export mechanisms. The system must operate within legally approved environmental performance limits.

5.3 Mass-Burn Incineration in the Project Scenario

For mass-burn incineration systems, waste is introduced into a combustion chamber with excess oxygen to ensure complete oxidation. The combustion temperature typically ranges between 850°C and 1100°C, ensuring thermal stability and minimizing incomplete combustion products.

Heat from combustion is transferred to a boiler, generating steam, which is used to produce electricity or industrial heat. The project scenario must document:

• Operating temperature ranges and residence times

• Boiler efficiency and steam generation rate

• Flue-gas treatment steps and reagent use

• Stack emissions monitoring requirements

• Bottom ash and fly ash handling procedures

Energy production and fossil carbon emissions from combustion are central elements of the project scenario.

5.4 Gasification and Pyrolysis Under the Project Scenario

Advanced thermal treatment technologies operate under restricted oxygen or oxygen-free conditions. In gasification, waste is converted into syngas through partial oxidation, whereas pyrolysis decomposes waste through thermal cracking in the absence of oxygen.

Although these processes differ in thermochemical pathways, both require a subsequent combustion step for the produced syngas or vapors to generate usable energy. Without this combustion and energy recovery, the project is ineligible.

The project scenario must describe:

• Reactor temperatures, oxygen ratios, and residence times

• Syngas composition and calorific value

• The combustion system used to oxidize syngas

• Energy recovery efficiency

• Material balance between char, gas, and condensates

These parameters influence fossil CO₂ emissions, auxiliary fuel consumption, and overall system efficiency.

5.5 RDF/SRF Co-Firing in Industrial Systems

In co-firing systems, refuse-derived fuel (RDF) or solid recovered fuel (SRF) replaces a portion of fossil fuels in industrial combustion units. The project scenario involves the production or procurement of these fuels and their delivery to industrial boilers, cement kilns, or power plants.

In the project scenario, the waste-derived fuel contributes thermal energy, reducing the use of coal, petroleum coke, fuel oil, or gas. The energy displacement and fossil-fuel baseline represent key parameters. The project scenario must characterize the waste-derived fuel, including:

• Moisture content and calorific value

• Proportion of biogenic vs. fossil carbon

• Ash content and combustion behavior

The industrial facility must demonstrate stable operation and measurable fossil-fuel displacement attributable to the use of RDF or SRF.

5.6 Energy Recovery Processes

Energy recovery is integral to the project scenario. The form of energy produced—electricity, heat, steam, or combinations—is recorded continuously or at frequent intervals to quantify displacement benefits.

In projects generating electricity, measured outputs from grid-compliant meters determine the total energy exported. For heat recovery systems, thermal energy delivered to industrial users or district heating networks must be measured through calibrated flow and temperature instruments.

The project scenario must maintain documentation of:

• Energy conversion efficiency

• Generator or turbine performance

• Operating hours and downtime

• Internal energy consumption attributable to WtE operations

Only net useful energy (exported or used to replace fossil sources) contributes to emission reduction calculations.

5.7 Greenhouse Gas Emissions in the Project Scenario

The project scenario includes all GHG emissions originating from facility operation. Key emissions include fossil CO₂ from combustion of plastic and synthetic materials, methane and nitrous oxide from thermal processes, and CO₂, CH₄, and N₂O associated with auxiliary fuels. Additional emissions may originate from reagent use in air-pollution control systems, internal electricity consumption, and residue handling activities.

Biogenic CO₂ is excluded from project emissions, following IPCC conventions. However, all other non-biogenic carbon flows must be quantified. Emission factors must be nationally approved where available or otherwise derived from international best practice.

5.8 Residue Generation and Handling

Thermal treatment results in bottom ash, fly ash, boiler ash, and flue-gas treatment residues. The project scenario must document the quantities, handling pathways, and final disposal or beneficial use of these materials. Residue treatment may generate project emissions through transport, stabilization processes, or landfill deposition. These emissions must be included when they are materially influenced by project activity.

5.9 Operational Performance Requirements

The project scenario must demonstrate sustained thermal stability, reliable energy recovery, and compliance with environmental regulations. Facilities experiencing persistent operational disruptions, flaring of syngas without energy recovery, or significant under-performance must suspend crediting until conditions are restored.

Thermal systems must be operated with clear process control indicators, including combustion temperature, oxygen concentration, steam production, and emission monitoring. These operational parameters ensure that the project scenario reflects the actual functioning of the WtE facility and provides the basis for accurate emission accounting.

5.10 Summary Interpretation of the Project Scenario

The project scenario represents a fully engineered Waste-to-Energy system operating under controlled conditions to thermally treat waste, generate energy, and reduce greenhouse gas emissions relative to baseline practices. It incorporates all material inputs, outputs, emissions, and energy transformations. By defining these parameters with scientific rigor and operational precision, PCS-TR-002 ensures that the project scenario accurately reflects the climate impact of the intervention and provides a reliable basis for calculating emission reductions.

Chapter 6 - Emission Reduction Calculation

6.1 Purpose of the Emission Reduction Calculation

The emission reduction calculation establishes the quantifiable climate benefit delivered by the Waste-to-Energy (WtE) project. It compares baseline greenhouse gas emissions with project emissions, producing a net value expressed in tonnes of CO₂-equivalent.

This chapter defines the methodological logic, equations, parameters, and assumptions required to determine emission reductions in a scientifically robust and conservative manner. It incorporates IPCC guidance for combustion emissions, methane generation modelling, and fossil fuel displacement, ensuring consistency with global best practice.

6.2 Core Emission Reduction Equation

Net emission reductions for year y are calculated as:

ER_y = BE_y − PE_y − LE_y

where:

• ER_y = Emission reductions in year y

• BE_y = Baseline emissions in year y

• PE_y = Project emissions in year y

• LE_y = Leakage emissions in year y

This structure ensures that both avoided emissions and project-induced emissions are fully captured.

6.3 Baseline Emissions (BE_y)

Baseline emissions arise from:

1. Methane generation from unmanaged decomposition of biogenic waste, and

2. Fossil fuel consumption in the baseline energy system that would have supplied equivalent energy to what the project provides.

6.3.1 Baseline Methane Emissions from Waste Disposal

Where the baseline involves landfilling or dumping, methane emissions are estimated using the IPCC First-Order Decay (FOD) model. Methane generation is distributed over time and depends on waste composition, degradable organic carbon, decomposition rate constants, and landfill management conditions.

Baseline methane emissions are calculated as the methane released to the atmosphere after accounting for cover oxidation.

6.3.2 Baseline Fossil Fuel Emissions for Energy Production

Where the project generates useful electricity or heat, the baseline corresponds to the fossil fuel or grid electricity displaced.

• For electricity: baseline emissions are the product of electricity displaced and the baseline grid emission factor.

• For heat or steam: baseline emissions are the product of heat displaced and the emission factor of the fossil fuel that would have been used.

Total baseline emissions aggregate methane and fossil fuel baseline components.

6.4 Project Emissions (PE_y)

Project emissions include fossil CO₂, methane, and nitrous oxide generated by thermal conversion systems, as well as auxiliary energy use and residue handling emissions. These emissions must be comprehensively accounted for to avoid overstating emission reductions.

Project emissions can be categorised into combustion emissions, auxiliary consumption, residue management, and any other direct sources influenced by the WtE facility.

6.4.1 Combustion Emissions from Fossil Carbon in Waste

The combustion of fossil-derived waste fractions (e.g., plastics, synthetic textiles, rubber) generates CO₂ that must be quantified.

PE_combustion = W_fossil,y × CF_fossil × oxidation_factor × (44/12)

where:

• W_fossil,y = Mass of fossil waste combusted in year y

• CF_fossil = Carbon content (fraction) of fossil waste components

• Oxidation factor = Fraction oxidized during combustion

• (44/12) = conversion from C to CO₂

Combustion-related CH₄ and N₂O emissions are calculated per IPCC combustion emission factors and converted to CO₂-equivalents.

6.4.2 Auxiliary Fossil Fuel Consumption

Auxiliary fuels such as diesel, natural gas, or fuel oil used for start-up burners, support firing, or internal transport contribute to project emissions and must be accounted for with appropriate fuel emission factors.

6.4.3 Electricity Consumption

Electricity consumed onsite reduces net emission reductions; it must be multiplied by the grid emission factor (or PCS conservative default) to convert to CO₂e.

6.4.4 Emissions from Residue Handling

Bottom ash, fly ash, boiler ash, and air-pollution control residues may require transport or landfilling. When these result in measurable emissions, they must be included.

6.4.5 Syngas Combustion for Gasification/Pyrolysis

For advanced thermal treatment, emissions associated with syngas combustion are calculated considering syngas composition, calorific content, and relevant non-CO₂ emission factors.

6.5 Energy Displacement Benefits

The primary benefit of WtE systems is displacement of fossil energy. Only net exported energy—after deducting internal consumption—contributes to emission reductions.

• Electricity displaced = Net electricity exported × baseline grid emission factor

• Heat displaced = Net thermal energy delivered × baseline fossil fuel emission factor

In co-firing systems, fossil fuel displacement is calculated as the reduced fossil fuel consumption attributable to RDF/SRF use. Only the biogenic fraction of RDF/SRF contributes to displacement credits.

6.6 Avoided Methane Emissions for Waste Diversion Projects

Where biogenic waste is diverted from dumping or landfilling into the WtE system, the avoided methane emissions represent a significant share of the climate benefit.

Avoided methane emissions are the baseline methane emissions that would have been generated and released to the atmosphere, prevented by diversion into thermal oxidation.

6.7 Total Project Emissions

Project emissions are aggregated across combustion, auxiliary fuels, electricity consumption, residue handling, and any other direct sources influenced by the project.

6.8 Net Emission Reductions

Combining all baseline and project terms:

ER_y = BE_y − PE_y − LE_y

This equation produces the final creditable emission reductions under PCS-TR-002.

6.9 Conservativeness Requirements

When multiple data sources exist, the methodology requires selection of values that result in lower emission reductions. This includes using lower heating values, higher fossil carbon fractions, more conservative grid emission factors, and default combustion factors when uncertainty exists. Where precise monitoring is not feasible, PCS defaults must be applied.

The conservativeness principle ensures that emission reductions are never overstated.

6.10 Summary Interpretation of the Calculation Framework

The emission reduction calculation combines avoided methane emissions, fossil energy displacement, and project emissions into a single coherent framework. The model supports multiple WtE technologies while ensuring a consistent scientific foundation. The structure is compatible with verification audits and can be implemented in automated calculation tools.

Chapter 7 - Monitoring Requirements

7.1 Purpose of Monitoring

The monitoring framework ensures that all data used to calculate emission reductions are accurate, complete, and verifiable throughout the crediting period. Waste-to-Energy (WtE) projects involve multiple complex processes—combustion, energy recovery, residue generation, and auxiliary energy use—each contributing to greenhouse gas emissions or reductions. Effective monitoring provides a reliable empirical foundation for emission calculations and ensures that project performance remains aligned with methodological requirements.

Monitoring must be continuous, systematic, and supported by calibrated instruments, documented procedures, and technically competent personnel. The system must be robust enough to withstand independent verification and regulatory inspection.

7.2 Monitoring Approach and Responsibilities

The project operator is responsible for implementing and maintaining a monitoring plan that covers all relevant emission sources and energy outputs. The plan must describe the monitoring methods, instruments, calibration procedures, quality assurance protocols, and data management systems.

Operators must ensure that instrumentation used to record energy outputs, fuel inputs, air emissions, and waste quantities remains in effective working condition. All monitoring activities must be documented in a way that allows verification of both raw data and aggregated results. Staff performing monitoring tasks should be trained in equipment operation, safety requirements, and data handling procedures.

7.3 Monitoring of Waste Inputs

Waste input data must be recorded accurately because they influence fossil carbon emissions, biogenic fractions, calorific values, and applicable baseline scenarios. Waste entering the WtE facility must be weighed using calibrated weighbridges.

Where waste is heterogeneous, periodic characterization studies are required to determine moisture content, ash content, lower heating value, and the proportion of biogenic and fossil carbon. These studies must be carried out with sufficient frequency to reflect seasonal or operational variability. For RDF or SRF projects, characterization must follow any relevant national standards or established analytical methods for identifying fuel properties.

Waste acceptance records must be maintained and traceable, including source information, vehicle data, and dates of delivery.

7.4 Monitoring of Combustion or Thermal Conversion Processes

Thermal performance directly affects emissions, residue characteristics, and energy recovery efficiency. The facility must monitor key combustion or reactor parameters such as chamber temperature, residence time, oxygen concentration, air flow, and fuel feed rates. These indicators must be recorded continuously or at frequent intervals consistent with equipment capabilities.

For gasification and pyrolysis processes, monitoring must include reactor temperature profiles, oxygen or steam injection rates, syngas composition, and syngas flow to the combustion system. Stable thermal operation is essential for ensuring complete oxidation of volatile compounds and minimizing methane or nitrous oxide emissions.

Documentation of operational hours, start-up periods, shutdowns, and abnormal events must be maintained, as these directly influence emission factors and crediting eligibility.

7.5 Monitoring of Energy Generation and Internal Consumption

Energy recovery is central to determining displacement benefits. Electricity generation must be measured using grid-certified meters located at the export point. These meters must be calibrated in accordance with national grid operator requirements or internationally recognized standards. Internal electricity consumption must also be metered, as it reduces net energy output.

For heat recovery systems, thermal output must be measured using calibrated flow meters and temperature sensors capable of determining the energy content of hot water or steam delivered to users. All operational hours during which energy is exported must be documented.

Energy consumption by air-pollution control systems, fans, pumps, conveyors, and auxiliary combustion equipment must also be monitored, as these contribute to project emissions.

7.6 Monitoring of Fossil Fuel and Auxiliary Material Use

Auxiliary fuels used for start-up, support firing, or reheating must be measured using appropriate meters or storage tank inventories. Emissions from these fuels form part of project emissions and must be included in the calculation.

Materials used in air-pollution control systems, such as activated carbon, lime, or ammonia, must be tracked because their production and use may contribute to overall emissions. The monitoring plan must include clear procedures for recording quantities, consumption rates, and relevant emission factors.

7.7 Monitoring of Air Emissions

Stack emissions from combustion systems must be monitored in accordance with regulatory requirements. Depending on the jurisdiction, this may involve continuous emission monitoring systems (CEMS) or periodic stack testing for CO₂, CO, CH₄, N₂O, NOₓ, SO₂, particulate matter, and heavy metals.

Where CEMS is installed, calibration, maintenance, and quality assurance procedures must be documented. Where stack testing is periodic, the monitoring frequency must comply with regulatory standards and be sufficient to capture representative operating conditions.

Measured emissions must be used where required by PCS-TR-002. If direct measurements are not available, default emission factors may be used only when permitted under the methodology.

7.8 Monitoring of Residue Streams

All residue streams generated by the project—bottom ash, fly ash, boiler ash, flue-gas treatment residues—must be monitored. Quantities must be recorded through weighing or volumetric estimation supported by density measurements. Residue transport, stabilization processes, and disposal pathways must be documented.

The monitoring plan must identify whether any residue management activity changes relative to the baseline scenario. If residues are diverted to beneficial uses, the process must be documented, although no displacement credit is awarded under PCS-TR-002.

7.9 Monitoring for Co-Firing Systems

Co-firing projects must monitor both the waste-derived fuel and the displaced fossil fuel. This includes the calorific value, mass flow, and carbon content of RDF/SRF and the corresponding fossil fuels. The monitoring system must allow for clear attribution of energy contributions, ensuring that fossil fuel displacement calculations are evidence-based.

Industrial operators must track kiln or boiler operating conditions, energy balances, and any process impacts attributable to the introduction of waste-derived fuels.

7.10 Data Quality, Calibration, and QA/QC

All monitoring instruments must be calibrated according to manufacturer specifications or national standards. Calibration records must be available for verification. Instruments operating outside tolerance must be repaired or replaced, and data from affected periods must be conservatively adjusted or excluded.

Data must be stored in a secure system with version control, back-up procedures, and audit trails. Any missing or anomalous data must be addressed using clearly defined procedures that prevent bias. Conservative substitution values must be applied where appropriate.

7.11 Monitoring Frequency and Reporting

Monitoring frequency must be sufficient to capture all relevant emission and energy parameters with accuracy. Continuous monitoring is required for major parameters such as electricity output, reactor temperature, and waste throughput. Periodic monitoring is acceptable for compositional analyses, fuel testing, and stack emissions when continuous systems are not available.

The project operator must compile an annual monitoring report that summarizes all required data, describes deviations from the monitoring plan, and provides all supporting documentation for emission reduction calculations.

7.12 Summary Interpretation

The monitoring framework ensures that emission reductions are grounded in empirical, verifiable data. By requiring systematic measurement of waste inputs, thermal performance, energy outputs, emissions, and residue streams, PCS-TR-002 maintains methodological integrity and ensures that credits issued reflect real climate benefits. The monitoring system must be sufficiently rigorous to withstand independent verification and regulatory scrutiny.

Chapter 8 - Data And Parameters

8.1 Purpose of This Chapter

This chapter defines the data and parameters required for emission reduction quantification under PCS-TR-002. It establishes which parameters must be monitored, which may be fixed or default values, and how data must be handled to ensure scientific integrity. Each parameter must be clearly defined, measurable, and associated with traceable evidence. Where uncertainty exists, conservative values must be selected to avoid overstating emission reductions.

8.2 General Requirements for Data Handling

All parameters used in emission reduction calculations must be supported by documented evidence and recorded consistently throughout the crediting period. Data must originate from calibrated instruments, verified laboratory measurements, or authoritative national or international sources.

Units must be applied consistently, and conversion factors must be transparently documented. Data quality must allow third-party auditors to reproduce all calculations using raw records. Missing or anomalous data must be addressed using conservative substitution methods and documented in monitoring reports.

8.3 Monitored Parameters

Monitored parameters are those that must be measured periodically or continuously because they materially influence project emissions or emission reductions. The subsequent sections describe key categories of monitored data.

8.3.1 Waste Quantity and Composition

The mass of waste received by the project must be recorded using calibrated weighbridges. Periodic waste characterization must determine the fraction of biogenic and fossil carbon, moisture content, ash content, and calorific value. Frequency of characterization must reflect operational variability and seasonality.

RDF and SRF require additional parameters such as mechanical specification, particle size, and homogeneity indices when relevant to combustion or displacement calculations.

8.3.2 Combustion and Reactor Operating Conditions

Temperatures, residence times, oxygen levels, and feed rates must be monitored because they influence emission factors, completeness of combustion, and thermal efficiency. For advanced thermal treatment systems, additional data such as syngas calorific value, hydrogen content, and moisture must be included.

8.3.3 Energy Generation and Export

Electricity generation must be measured with certified meters, recorded at the point of export, and logged at intervals that capture operational fluctuations. Internal electricity consumption must also be measured.

For heat recovery systems, flow rates and temperature differentials must be monitored to determine net useful thermal energy. Turbine or generator efficiency data may be required to support calculations of net energy displacement.

8.3.4 Emissions From Combustion

Stack emissions of CO₂, CH₄, and N₂O must be monitored when continuous or periodic measurement is required by regulation or by the methodology. Additional pollutants such as NOₓ, SO₂, and particulate matter may require monitoring for regulatory compliance, but they only enter emission calculations when they are tied to GHG components.

8.3.5 Auxiliary Fuel and Material Use

Auxiliary fuels such as diesel, natural gas, or fuel oil must be monitored through meter readings or tank inventories. Consumption of reagents used in flue-gas treatment—such as activated carbon, lime, or ammonia—must be recorded when they materially contribute to emissions.

8.3.6 Residue Quantities

Bottom ash, fly ash, and other residues must be weighed or volumetrically measured. Residue moisture content and composition may be necessary when emissions arise from downstream handling or disposal.

8.4 Calculated Parameters

Calculated parameters are derived from monitored data using equations specified in the methodology. They include internal energy balances, fossil carbon oxidation calculations, displaced fossil fuel equivalents, and methane generation estimates using the IPCC FOD model.

Examples include:

• Net electricity exported after deducting internal consumption

• Net thermal energy delivered

• Fossil CO₂ emissions based on the mass and carbon content of fossil waste fractions

• Avoided methane emissions applying baseline methane generation parameters

Calculated parameters must be traceable to their underlying monitored inputs.

8.5 Default Parameters and Fixed Values

Certain parameters may use standardized default values when direct measurement is impractical or when regulatory norms provide stable references. Default values must originate from authoritative sources such as the IPCC Guidelines, national inventories, or PCS-approved datasets.

Examples include the global warming potential of methane and nitrous oxide, default methane correction factors for baseline landfills, and standard emission factors for auxiliary fuels. Default values must be applied conservatively and updated when new guidance or scientific revisions become available under PCS rules.

Where national values differ from international defaults, the value yielding lower emission reductions must be selected unless evidence supports a site-specific adjustment.

8.6 Parameters Requiring Laboratory Analysis

Some parameters require periodic laboratory testing. These include the carbon content of waste fractions, ultimate analysis of RDF/SRF, lower heating values, and chemical properties of residues. Laboratories performing these tests must be certified or accredited, and analytical methods must follow recognized standards.

Laboratory results must document sample preparation procedures, testing dates, analytical instruments used, and uncertainty margins. These records must be retained in support of verification.

8.7 Data Frequency Requirements

Monitoring frequencies must align with the significance of each parameter. Continuous monitoring is required for high-frequency variables such as electricity output, combustion temperatures, or waste feed rates. Daily or weekly monitoring may be acceptable for auxiliary fuel consumption or reagent use. Waste composition and calorific value testing must occur at intervals sufficient to capture operational variability.

Where monitoring intervals differ from the default methodological requirement, the project must justify the alternative approach and demonstrate that the resulting uncertainty is conservative.

8.8 Data Quality and Uncertainty Management

Data must meet minimum quality thresholds to support the credibility of emission reduction claims. Instruments must be calibrated, and calibration records must be retained. Data anomalies—such as negative values, operational inconsistencies, or missing records—must be flagged and corrected using conservative substitution rules.

Uncertainty must be quantified for parameters that significantly influence emission reductions, such as waste composition, calorific values, or stack emission measurements. When uncertainty cannot be reduced through improved monitoring, PCS requires the application of conservative emission factors or correction coefficients to ensure the integrity of calculated reductions.

8.9 Data Archiving and Traceability

All monitored, calculated, and default parameters must be archived for a period defined by PCS governance rules. Data must be stored in a secure and accessible format, with clear version control to support third-party verification. The project operator must maintain traceable documentation linking raw data, intermediate calculations, and final emission reduction outputs.

Records related to waste characterization, laboratory tests, calibration certificates, and energy meter logs must be preserved in their original or certified format.

8.10 Summary Interpretation

The data and parameter framework ensures that emission reduction calculations are grounded in defensible, high-quality evidence. By establishing clear definitions for monitored, calculated, and default parameters, PCS-TR-002 provides transparency and methodological rigor. Proper implementation of this framework enables consistent verification and ensures that carbon credits issued under this methodology represent real and measurable climate benefits.

Chapter 9 - Environmental And Social Safeguards

9.1 Purpose of Safeguard Requirements

Waste-to-Energy projects must operate in a manner that protects the environment, human health, and surrounding communities. Thermal treatment facilities can produce air pollutants, residues, noise, traffic, and occupational hazards if not properly managed. This chapter establishes mandatory safeguards to ensure that WtE projects generate climate benefits without causing unintended social or environmental harm. Safeguards form a core requirement for project eligibility and ongoing crediting under PCS-TR-002.

9.2 Regulatory Compliance

Projects must comply with all applicable environmental, health, and safety regulations in the host country. Compliance includes obtaining the necessary environmental impact assessments, construction and operation permits, emissions authorizations, and residue management approvals. Compliance must be demonstrated at validation and maintained throughout the crediting period. Any unresolved regulatory non-compliance—such as permit violations, excessive stack emissions, or improper waste handling—must result in suspension of crediting until corrective action is verified. Projects operating without required approvals are not eligible under PCS-TR-002.

9.3 Air Quality and Emission Control

Thermal treatment systems generate combustion gases containing regulated pollutants such as particulate matter, nitrogen oxides, sulfur dioxide, carbon monoxide, acid gases, metals, and organic compounds. Air-pollution control systems must be designed and operated to reduce these emissions to within permitted limits.

The project must maintain records of stack emission measurements, either through continuous monitoring systems or periodic testing as required by regulation. Exceedances must be documented and corrective measures implemented immediately. Persistent exceedances may disqualify the project from receiving credits.

Emission control equipment—such as bag filters, electrostatic precipitators, scrubbers, or selective catalytic reduction units—must be maintained in operable condition, with clear procedures for maintenance and inspection.

9.4 Residue Management and Environmental Protection

Thermal treatment produces bottom ash, boiler ash, fly ash, and air-pollution control residues. These materials may contain contaminants requiring careful handling. The project must store, transport, and dispose of residues in accordance with national regulations. If residues are landfilled, the facility must use a licensed disposal site with appropriate environmental protection measures. If residues are beneficially used—such as in construction materials—supporting documentation must confirm compliance with relevant standards.

Ash analysis must be conducted periodically to determine chemical composition, leaching behavior, and suitability for disposal or reuse. Improper residue handling may result in environmental contamination and must be addressed immediately.

9.5 Noise, Odor, and Traffic Management

WtE facilities may generate noise from turbines, fans, and waste handling equipment. They may also contribute to local traffic due to waste transport vehicles. Project operators must implement mitigation measures—such as acoustic barriers, optimized transport schedules, and controlled tipping practices—consistent with regulatory requirements and good industry practice.

Odor control systems must be implemented where waste reception or pre-processing areas could generate nuisance odors. Negative-pressure reception halls, biofilters, or activated carbon systems are commonly required. Projects must ensure that these systems operate effectively to minimize community impacts.

9.6 Worker Health and Safety

Thermal treatment facilities present occupational hazards, including high temperatures, pressurized systems, moving machinery, exposure to chemicals, and electrical risks. The project must implement a comprehensive occupational health and safety management system, including hazard identification, training, emergency response procedures, use of personal protective equipment, and routine safety inspections.

Incidents involving injury, equipment failure, or hazardous conditions must be documented and investigated. Corrective measures must be implemented promptly to prevent recurrence. Safety performance must be included in annual monitoring reports.

9.7 Community Engagement and Grievance Mechanisms

Projects must engage with communities potentially affected by facility activities. Engagement measures may include public consultations, information sharing, and open communication channels. A grievance mechanism must be available to community members to express concerns related to noise, traffic, odor, safety, or environmental performance.

The project operator must document grievances received, actions taken, and their outcomes. Unresolved grievances or repeated complaints indicating significant impacts may require additional mitigation or review.

9.8 Protection of Vulnerable Populations

Where project activities occur near residential areas, schools, hospitals, or other vulnerable groups, additional safeguards may be required. These may include enhanced air-quality monitoring, restricted operating hours, noise suppression technologies, or alternative waste transport routes.

Projects must demonstrate that no disproportionate burden falls upon vulnerable communities. If impacts are identified, mitigation measures must be incorporated into project operations.

9.9 Environmental Impact Assessment (EIA) Requirements

An environmental impact assessment must be conducted when required by national law or when project characteristics indicate a significant potential for environmental effects. The EIA must evaluate impacts on air, water, soil, biodiversity, noise, traffic, and social dimensions. Mitigation measures proposed in the EIA become binding conditions of eligibility under PCS-TR-002.

Where EIAs are not legally required, the project must still provide an environmental review demonstrating that operational impacts have been assessed and mitigated to acceptable levels.

9.10 Ongoing Monitoring of Safeguard Performance

Safeguards must be monitored continuously or at appropriate intervals. This includes tracking regulatory compliance status, recording results of air emissions tests, surveying community concerns, and reviewing worker safety performance.

Monitoring results must be included in the project’s annual report. Any safeguard non-compliance that affects environmental integrity must be rectified immediately, and crediting may be suspended until conditions return to compliance.

9.11 Summary Interpretation

Environmental and social safeguards ensure that Waste-to-Energy projects deliver climate benefits while upholding strong environmental protection and public welfare. By requiring compliance with regulatory standards, effective pollution control, safe residue management, worker protections, and transparent community engagement, PCS-TR-002 maintains a high level of integrity and ensures that WtE interventions do not create adverse impacts while generating emission reductions.

Chapter 10 - Uncertainty And Conservativeness

10.1 Purpose of Uncertainty and Conservativeness Requirements

Waste-to-Energy projects involve multiple data streams—waste composition, combustion performance, energy generation, emission factors, and baseline modeling—each introducing varying degrees of uncertainty. The purpose of this chapter is to ensure that uncertainties do not lead to overstated emission reductions. PCS-TR-002 requires the explicit identification of uncertainty sources and the consistent application of conservative assumptions, thresholds, and correction factors.

The principles outlined here apply across all methodological steps and ensure that final emission reduction estimates err on the side of underestimation rather than overestimation, preserving the credibility of PCS credits.

10.2 Sources of Uncertainty in WtE Systems

Uncertainty arises from technical, operational, data-related, and methodological factors. The most significant sources include:

• Waste Composition: The heterogeneous nature of municipal solid waste and RDF/SRF introduces uncertainty in biogenic and fossil carbon fractions, calorific values, and moisture content. Variability may follow seasonal patterns, socio-economic factors, or changes in waste collection practices.

• Combustion Conditions: Variability in temperatures, air flow, and feed rates can influence combustion efficiency, non-CO₂ emissions, and the proportion of unburned hydrocarbons.

• Energy Generation: Fluctuations in generator performance, turbine efficiency, and internal consumption influence net energy displacement calculations.

• Emission Factors: Default emission factors for methane, nitrous oxide, and fossil fuels may differ across national inventories, IPCC sources, or operator measurements. Selection of these factors can significantly affect project emission estimates.

• Baseline Modeling: Uncertainty in baseline waste disposal practices, landfill decay rates, methane oxidation, and fossil fuel displacement pathways can influence the magnitude of avoided emissions.

Each uncertainty source must be addressed using conservative, scientifically defensible methods.

10.3 Conservativeness in Waste Composition and Carbon Fractions

When waste composition data are incomplete or show high variability, fossil carbon fractions must be assumed at the upper bound of plausible ranges, and biogenic fractions at the lower bound. Lower heating value estimates must use the most conservative available data, particularly for RDF/SRF fuels. If laboratory analysis results conflict with operational observations, conservative interpretations must be applied until discrepancies are resolved.

When only periodic sampling is conducted, the methodology requires that samples be treated as minimum-bound estimates for biogenic content and calorific quality.

10.4 Conservativeness in Combustion and System Efficiency

Incomplete combustion of fossil waste fractions increases fossil CO₂ emissions and must be accounted for using conservative combustion efficiency assumptions. If operational conditions deviate from stable thermal performance, non-CO₂ emission factors must default to conservative IPCC values rather than facility-specific estimates.

Energy conversion efficiency must be based on conservative averages rather than peak operational performance. Internal energy consumption may vary; therefore, meters must default to the higher of the measured values or conservative thresholds if operational anomalies occur.

10.5 Conservativeness in Baseline Fossil Fuel Displacement

When calculating emission reductions from electricity or heat production, the emission factor for displaced fossil energy must be selected conservatively. If several grid emission factors are available—such as long-term averages, marginal factors, or published national values—the lowest defensible value must be used.

For thermal displacement, project developers must use conservative fossil fuel emission factors and efficiency values. Claims based on marginal or speculative fuel-switching scenarios are not permitted. In co-firing projects, displacement must reflect the fossil fuel actually used in the baseline, not hypothetical alternatives.

10.6 Conservativeness in Avoided Methane Emissions

When modeling avoided methane generation from baseline landfills or dumpsites, uncertainty in waste quantities, degradable organic carbon, decay constants, and methane correction factors must be addressed conservatively.

If data for historical waste deposition are incomplete, the methodology requires the use of lower-bound waste quantities and decay parameters that yield lower baseline methane generation. Oxidation values must be minimal unless robust evidence indicates otherwise.

In no case may the baseline assume methane capture in landfills unless such systems are already installed and operational or legally mandated.

10.7 Treatment of Missing or Anomalous Data

Periods with missing combustion, energy, or waste data must be handled conservatively. Substitution values must reflect the worst-case scenario for emission reductions. For example, missing energy generation data must default to zero net export, and missing fossil fuel consumption data must assume the upper plausible consumption level for the period.

Data gaps arising from equipment malfunction, meter failure, or operational disruptions must be documented, and corrective actions must be applied promptly. Prolonged data loss may require exclusion of affected periods from crediting.

10.8 Monte Carlo or Statistical Approaches (Optional)

For large-scale projects where uncertainty materially affects emission reductions, developers may apply statistical techniques—such as Monte Carlo simulations—to quantify uncertainty ranges. If applied, the methodology requires selecting the lower 90% confidence bound as the creditable emission reduction value. This ensures that uncertainty does not inflate carbon credit issuance.

The use of statistical approaches does not replace the need for conservative parameter selection but may complement it in complex systems.

10.9 Conservativeness in Calculation Tools

PCS-approved calculation tools must incorporate conservative defaults and automated correction factors. Where multiple datasets are available for a parameter, the tool must default to the value yielding the lowest emission reduction.

Formula structures must prevent unintended over-crediting, including preventing negative project emissions during abnormal operating conditions. All embedded parameters must be transparent to auditors.

10.10 Summary Interpretation

Uncertainty is inherent in Waste-to-Energy systems due to the complexity of waste streams, combustion processes, and energy systems. PCS-TR-002 manages uncertainty through a structured and consistent conservativeness framework that safeguards against inflated emission claims. By applying conservative parameter selection, strict data quality rules, and transparent correction procedures, the methodology ensures that emission reductions credited under PCS represent real, measurable, and verifiable climate benefits.

Chapter 11 - Leakage Assessment

11.1 Purpose of Leakage Assessment

Leakage refers to greenhouse gas (GHG) emissions that occur outside the project boundary but are caused by, or directly linked to, project activities. For Waste-to-Energy (WtE) systems, leakage may arise from changes in waste transport patterns, displacement of waste from other facilities, upstream emissions from producing auxiliary materials, or shifts in fuel use. This chapter establishes the conditions under which leakage must be assessed and quantified, and defines which leakage sources are relevant for projects applying PCS-TR-002. The overarching principle is to ensure that all project-related emissions are captured so that credited emission reductions reflect net climate benefits.

11.2 Types of Leakage Relevant to WtE Projects

Leakage sources relevant to WtE systems fall into several categories. Their relevance depends on project design, location, feedstock logistics, and the baseline scenario. While not all categories will apply to every project, each must be considered.

• Displacement Leakage: If the project diverts waste from another facility that would otherwise manage it in a lower-emission pathway, leakage may occur. For example, if waste previously sent to a semi-managed landfill with methane capture is diverted to a mass-burn facility, the project may inadvertently increase emissions unless carefully assessed.

• Transport Leakage: Changes in transport distances for waste delivery or residue disposal may cause incremental fuel consumption. If the WtE facility is farther from waste generation points than the baseline disposal site, additional transport emissions must be included.

• Upstream Leakage from RDF/SRF Production: When the project includes waste preprocessing to produce RDF or SRF, emissions generated from shredding, sorting, drying, or pelletizing may constitute leakage unless these activities occur within the project boundary and are already counted as project emissions. If preprocessing takes place offsite and outside the project boundary, upstream emissions must be evaluated.

• Auxiliary Material Leakage: Some WtE technologies require reagents—such as lime, sodium bicarbonate, ammonia, or activated carbon—for flue-gas treatment systems. If the project significantly increases the production or use of these materials compared to the baseline, the associated upstream emissions may constitute leakage.

• Fuel-Shifting Leakage in Co-Firing Systems: When waste-derived fuels displace fossil fuels in industrial boilers or kilns, there is a possibility that the displaced fossil fuel may be used elsewhere rather than being eliminated. PCS applies conservative rules that prevent crediting unless displacement is clearly demonstrated. Only displacement that results in an actual reduction in fossil fuel procurement is recognized.

11.3 Leakage Screening

Projects must perform a leakage screening assessment to identify relevant sources. Screening involves reviewing baseline and project logistics, fuel pathways, and material flows. The assessment must describe:

• Whether waste transport distances change

• Whether alternative facilities experience reduced waste throughput

• Whether upstream preprocessing activities occur outside the boundary

• Whether displaced fuels may be used elsewhere

• Whether the supply chain for auxiliary reagents changes

Leakage sources that are screened out must have clear justification. If evidence is inadequate, PCS requires conservatively assuming the leakage source is present.

11.4 Quantification of Transport Leakage

Transport leakage occurs when project activities cause an increase in fuel consumption for waste or residue transport relative to the baseline. Quantification requires:

1. Determining baseline and project transport distances.

2. Estimating vehicle fuel consumption per kilometer.

3. Multiplying fuel consumption by emission factors for diesel or gasoline.

Transport leakage is calculated as the difference in transport emissions between project and baseline. If project distances are shorter than baseline distances, no negative leakage is applied; the value is set to zero for conservativeness.

11.5 Quantification of Leakage from Upstream Preprocessing

When RDF/SRF is produced in offsite facilities not included in the project boundary, emissions from mechanical treatment, drying, or pelletization may constitute leakage.

Quantification involves:

• Electricity consumption

• Fuel use for thermal drying

• Emissions associated with auxiliary materials used in preprocessing

If preprocessing emissions are already accounted for within the project boundary, no leakage is applied to avoid double counting.

11.6 Leakage from Displaced Waste or Landfill Operations

If the project leads to reduced waste inputs at another waste treatment facility, such as a landfill, the baseline emissions of that facility may change. Leakage must be assessed when:

• Waste is diverted from a landfill with gas collection

• Waste is diverted from composting or anaerobic digestion facilities

• Waste previously handled in a lower-emission system is redirected

In such cases, avoided emissions at the baseline facility must be compared with project emissions to identify potential leakage. Only increases in external emissions constitute leakage.

For waste diverted from unmanaged dumpsites or uncontrolled landfills, no leakage is applied because those sites do not provide emissions benefits in the baseline.

11.7 Upstream Leakage from Auxiliary Reagents

If the project significantly increases the use of chemical reagents or consumables relative to the baseline, upstream emissions from producing these materials must be included. Examples include activated carbon for dioxin removal, lime for acid gas neutralization, and ammonia for NOₓ control.

Leakage is calculated using the incremental quantity of reagents multiplied by appropriate upstream emission factors. Only incremental reagent use relative to the baseline is counted.

11.8 Leakage from Rebound or Market Effects

In co-firing systems, displaced fossil fuels may re-enter the market and be combusted elsewhere. While theoretically possible, such rebound effects are rarely traceable. PCS applies a simplified rule: displacement must be demonstrated through procurement records, and only reductions in actual fossil fuel purchases count toward emission reductions.

No additional market leakage is added unless strong evidence indicates that project activity creates identifiable upstream or downstream emissions outside the boundary.

11.9 Aggregation of Leakage Sources

All relevant leakage sources for year y must be combined:

LE_y = Transport_leakage_y + Preprocessing_leakage_y + Auxiliary_reagent_leakage_y + Other_relevant_leakages_y

If a potential leakage source cannot be quantified with reasonable accuracy, the methodology requires a conservative estimation or the exclusion of the associated emission reduction claim.

11.10 Summary Interpretation

Leakage assessment ensures that Waste-to-Energy projects do not create hidden greenhouse gas impacts outside the direct project boundary. By evaluating transport impacts, upstream preprocessing, auxiliary material use, and changes to other waste facilities, PCS-TR-002 ensures that emission reductions are net of all project-induced external emissions. Leakage rules under this methodology follow strict conservativeness principles, ensuring that credits issued represent genuine climate benefits rather than shifted emissions.

Chapter 12 - Annexes

12.1 Purpose of the Annexes

The annexes provide detailed equations, parameter tables, reference values, monitoring templates, and decision-support tools required to apply PCS-TR-002 in practice. While the main text outlines the conceptual and methodological framework, the annexes translate these requirements into operational formats that can be used for calculations, verification, and implementation.

These annexes are integral to the methodology and must be applied consistently. Any updates to annex values (e.g., GWPs, national emission factors) must follow PCS revision protocols.

12.2 Annex A - Equations for Emission Reduction Calculations

This annex compiles all equations referenced across Chapters 4–11, including:

• A.1 Baseline Methane Generation (FOD Model)

• A.2 Baseline Methane Released to Atmosphere

• A.3 Baseline Methane Emissions

• A.4 Baseline Electricity Displacement

• A.5 Baseline Thermal Displacement

• A.6 Fossil CO₂ Emissions from Project Combustion

• A.7 CH₄ and N₂O from Combustion

• A.8 Auxiliary Fuel Use

• A.9 Electricity Consumption

• A.10 Residue Handling

• A.11 Syngas Combustion (ATT Systems)

• A.12 Transport Leakage

• A.13 Total Emission Reductions

12.3 Annex B - Default Parameters and Reference Values

This annex provides standardized values that may be used when site-specific data are unavailable. These values must be applied conservatively.

B.1 Global Warming Potentials (GWP100)

• CH₄: 28 (or updated value per PCS vintage rules)

• N₂O: 265 (subject to PCS updates)

B.2 IPCC Waste Parameters

• DOC defaults by region (ranges provided)

• DOC_f = 0.5 (unless regional studies indicate otherwise)

• MCF values for unmanaged, semi-managed, and managed landfills

• Decay constants (k) based on climate zone

• Methane fraction (F) = 0.5

B.3 Default Emission Factors for Auxiliary Fuels

Provided separately for diesel, gasoline, natural gas, LPG, heavy fuel oil, and refinery gas.

B.4 Default Emission Factors for Cement Kiln or Industrial Fuels

Includes coal, petcoke, fuel oil, and natural gas.

B.5 Standard Efficiency Values

Applies when direct measurements are missing:

• Baseline fossil boiler efficiency

• Turbine default efficiencies

• Heat recovery coefficients

12.4 Annex C - Monitoring Templates

Monitoring templates support consistent data capture. Key templates include:

C.1 Waste Input Log Template

• Date

• Source

• Vehicle ID

• Weight (kg)

• Waste Type

• Characterization batch ID

C.2 Energy Output Monitoring Sheet

• Electricity exported

• Electricity consumed

• Steam production

• Flow and temperature measurements

C.3 Combustion and Reactor Log

• Temperature

• Air/O₂ input

• Feed rate

• Operating hours and anomalies

C.4 Residue Management Log

• Bottom ash (t)

• Fly ash (t)

• Boiler ash (t)

• Leaching test ID

• Disposal or reuse location

C.5 Auxiliary Fuel and Reagent Log

• Fuel type

• Quantity

• Meter or invoice reference

All templates must be maintained electronically with timestamped entries and cross-referenced calibration certificates.

12.5 Annex D - Decision Tree for Technology Applicability

Decision nodes determine applicability:

• Node 1: Is waste thermally treated in a controlled chamber? If NO → not eligible.

• Node 2: Is useful energy recovered? If NO → not eligible.

• Node 3: Is waste-derived syngas combusted to generate energy? If YES → apply ATT provisions.

• Node 4: Is RDF/SRF co-fired in an industrial furnace? If YES → apply co-firing provisions.

• Node 5: Does the project require waste preprocessing? If YES → include preprocessing requirements.

• Node 6: Does the project displace fossil energy? If YES → apply fossil energy displacement baseline.

• Node 7: Does waste diversion avoid landfill methane generation? If YES → apply landfill methane baseline; if NO → use only displacement baseline.

Documentation required includes system design, metering plans, fuel logs, preprocessing records, and baseline disposal evidence.

12.6 Annex E - Worked Example: Emission Reduction Calculation

A numerical example illustrates complete application of the methodology, showing:

• Baseline methane modeling (FOD)

• Electricity displacement

• Fossil CO₂ emissions from combustion

• Auxiliary fuel impacts

• Residue disposal emissions

• Transport leakage calculations

The worked example supports auditors and project developers in applying methodology steps consistently.

12.7 Summary Interpretation

The annexes serve as practical tools supporting implementation of PCS-TR-002. By providing equations, default parameters, monitoring templates, and decision-support structures, the annexes ensure that Waste-to-Energy projects can be validated, monitored, and verified effectively. These materials form an essential complement to the methodology’s conceptual framework and are integral to ensuring accuracy, transparency, and conservativeness in emission reduction accounting.