FUENTES DE INFORMACIÓN

3.2.9.1 Source Category Description

The emissions that are included in this source category arise from the following sectors:

• _{Commercial/Institutional} – emissions from fuel combustion in commercial and institutional buildings;

• _Residential – emissions from fuel combustion in households (including household and garden machinery); and

• Agriculture/Forestry/Fishing – emissions from fuel combustion in these sectors, including both stationary and mobile sources.

Emissions from the burning of municipal solid waste (MSW), sewage gas and landfill gas to generate heat were previously reported under CRF source category 1A4, although these have been reallocated to 1A1 for the 2012 submission, following the advice from the ERT. Emissions from stationary railway sources are reported under 1A4a Commercial/Institutional. Stationary railway sources include emissions from the combustion of burning oil, fuel oil and natural gas used by the railway sector.

3.2.9.2 Methodological Issues

The inventory methodology includes a reallocation of gas oil from the industrial, commercial and public sectors to off-road vehicles and mobile machinery. However, the GHGI still maintains consistency with the total UK consumption of gas oil/DERV reported in DUKES. Emissions of both direct and indirect greenhouse gases for other sources are primarily calculated using national activity data, taken from DUKES, and emission factors. Emissions from off-road mobile sources including agricultural and other machinery are estimated based on recent research by AEA, which includes some minor modifications to fuel use allocations from DUKES. See Section A.3.3.7 for further details.

Emissions from fishing vessels are included in this sector. These are compiled alongside shipping emissions, and the method is described in Section 3.2.8.

3.2.9.3 Uncertainties and Time Series Consistency

The Approach 1 (error propagation) uncertainty analysis in Annex 7 provides estimates of uncertainty according to IPCC source category and fuel type.

Most of the core activity data for this source category is derived from the DECC publication the Digest of UK Energy Statistics. Section 3.5 provides further general information about

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the time series consistency of activity data in this publication, and provides more general comments on the approaches used to ensure time series consistency in source category 1A.

Table 3-6 summarises the time series consistency of emission factors used in source category 1A4.

Table 3-6 Time series consistency of emission factors of direct GHGs used in source category 1A4

GHGs Source

category Fuel types Comments on time series consistency

Carbon 1A4 All fuels EFs vary somewhat across time series based on _{the UK carbon factor review in 2004.} CH4, N2O 1A4 All fuels

Nearly all EFs are constant over the entire time series, with limited use of time-varying EFs due to fuel variability or technological developments.

3.2.9.4 Source Specific QA/QC and Verification

This source category is covered by the general QA/QC of the greenhouse gas inventory in

Section 1.6.

3.2.9.5 Source Specific Recalculations

Emissions from the burning of municipal solid waste (MSW) to generate heat were previously reported under CRF source category 1A4. These have now been reallocated to sector 1A1a for the 2012 submission, following the advice from the ERT.

A review has been performed this year on the allocation of gas oil to different sectors. Gas oil is used in both off-road transport and machinery diesel engines, and as a fuel for stationary combustion. The varied use of this fuel complicates the means of allocating consumption across the wide range of sectors that use the fuel in the inventory. DUKES provides a breakdown of gas oil consumption in different industry and other sectors, but with high uncertainty and DUKES is unable to distinguish between use of the fuel for stationary combustion and off-road machinery, a distinction which is necessary for the inventory. This review mainly affects sectors 1A2 and 1A4 although include a reallocation of petrol and diesel from road transport to off-road machinery; these changes are explained fully in Annex 3 (Section A3.3.8).

Some small changes have been made to the emissions from the OTs and CDs. Discussions with the Gibraltar Environment Agency have shown that emissions from domestic combustion do not occur and those emissions have now been removed from the inventory. A small correction has also been made to estimates of LPG use in the CDs.

3.2.9.6 Recalculation by Gas

The following section describes the main changes that have occurred in sector 1A4 per pollutant since the publication of the 2009 inventory (2011 NIR). Comparisons are made between the current inventory (1990-2010) and the previous inventory (1990-2009) for the year 2009.

3.2.9.6.1 Carbon Dioxide (CO2)

• Overall CO2 emissions from 1A4 decreased by 469 Gg CO2. The main reasons for

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• The largest revision to emissions in his sector is a decrease in emissions of 459 Gg CO2 due to a revision of domestic natural gas consumption in DUKES (DECC, 2011).

• There has been a reallocation of combustion of MSW for heat generation to 1A1; this has caused a decrease of 38 Gg CO2.

• Small revisions have also been made to domestic combustion data for the crown dependencies and overseas territories, based on updated statistics.

• The remaining differences are due to a combination of DUKES revisions and gas oil reallocations following a recent gas oil allocation review. See Annex 3 and Table 10-1 for more information.

3.2.9.6.2 Methane (CH4)

• There was an overall decrease in emissions from 1A4 of 8.0 Gg CH4. The main

causes of these changes are revisions and reallocations to activity data as described above, plus a reallocation of sewage gas and landfill gas to 1A1 in response to a recommendation by the UNFCCC’s expert review.

• Minor changes to emission factors for fuel oil and anthracite have been made due to revisions to GCVs.

3.2.9.6.3 Nitrous Oxide (N2O)

• There was an overall decrease in emissions from 1A4 of 2.0 Gg N2O. The main

causes of these changes are revisions and reallocations to activity data as described above, plus a reallocation of sewage gas and landfill gas to 1A1 in response to a recommendation by the UNFCCC’s expert review.

• Minor changes to emission factors for coal, coke, fuel oil and anthracite have been made due to revisions to GCVs.

3.2.9.6.4 Nitrogen Oxides (NOx)

• There have been no significant recalculations for this version of the inventory.

3.2.9.6.5 Carbon Monoxide (CO)

• There have been no significant recalculations for this version of the inventory.

3.2.9.6.6 Sulphur Dioxide (SO2)

• Estimates of emissions from domestic coal combustion have decreased by 2 Gg due to a revision in the emission factor.

3.2.9.6.7 Volatile Organic Compounds (VOC)

• There has been a significant reduction in the emission estimate for domestic combustion of wood and peat following a revision to the emission factor, with emissions decreasing by 19 Gg

3.2.9.7 Source Specific Planned Improvements

Research is planned into the energy data for used for public sector emissions, although the scope of this work is not yet finalised. Emission factors and activity data are kept under review. For full details of the improvement programme see Section 1.2.2.5.

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