Understanding CDM Methodologies - SuSanA

Landfill gas capture and flaring activities
Two Components:
Methane
Reduction from
Venting and
Displacement of
Grid Electricity
Ex ante Estimate
of Baseline
Emissions
required
Baseline Emissions
Monitoring ex
post through Gas
flares/used
Emissions reductions stemming from projects that only capture and flare the
landfill gas correspond to the amount of methane destroyed/combusted by
the project, minus the amount of methane that would have been destroyed/
combusted had the project not occurred, minus the emissions attributed to
the energy and/or fuel consumed throughout the development and operation
of the project. These include for instance emissions attributable to the use
of on-site generator during the early development stage of the project,
emissions stemming from the operation of the gas pumping system, and/or
emissions attributable to the use of electrical power to operate the project.
Project proponents should provide an ex ante estimate of the emissions
that would be released from the landfill through time had the CDM project
activity not occurred. Project proponents can estimate ex ante emissions
using the latest version of the “Tool to determine methane emissions avoided
from dumping waste at a solid waste disposal site” (see box 29).
The project’s emissions reductions are measured ex post by monitoring
the quantity of methane flared and gas used to produce energy when
applicable, and the total quantity of methane captured. More specifically,
project participants must compare the sum of the methane quantities fed to
the flare(s), to the power plant(s) and to the boiler(s) with the total metered
quantity of methane captured from the landfill site. The smallest value of the
two is to be considered as the project’s emissions reductions.
Box 29: The “Tool to determine methane emissions avoided from dumping
waste at a solid waste disposal site” 264
Application
of First Order
Decay Model for
Baseline Emissions
Estimate
Methane emissions that would have been generated by solid waste disposed in a
landfill site in the absence of the project activity are calculated using a first order
decay (FOD) model. In a nutshell, the FOD model differentiates between types
of waste with different decay rates and different fractions of organic carbon.
In addition, it takes into account the effects of different climatic conditions and
waste management practices. Once the composition and the volume of the
landfill’s waste stream are assessed, the FOD model uses these parameters to
estimate the yearly methane emissions that would occur in the landfill site in the
absence of the project activity.
The FOD model can be applied in cases where the waste that would be disposed
can clearly be identified. Since the project’s baseline scenario must be reassessed
at the beginning of each crediting period, several parameters in the model can be
changed to account for changes in the baseline scenarios. For more information
on how to apply the FOD model, please refer to the latest version of the Tool.
Landfill gas capture activities to produce energy or supply gas
Emission reductions from projects that capture landfill gas and produce
energy (either electricity or thermal energy) or supply natural gas stem from
the net amount of methane destroyed/combusted by the project plus the
amount of fossil-fuel energy displaced by the production of energy or the
supply of gas (in CO 2
eq.), minus the emissions attributed to the energy
and/or fuel consumed by the project. If the project uses electricity for its
operations and provides electricity to the grid, only the net quantity of
electricity supplied to the grid should be accounted.
230
EB 26, Annex 14.
87