What are the conversion factors used to calculate TPER?

TPER is calculated by applying the following conversion factors to each element of the organisation’s total final consumption. The conversion factors can change from year to year. The conversion factor for electricity is especially prone to change.

Energy Type2015 Primary Energy Conversion Factor: TFC to TPER
Electricity Imports2.113
Onsite Generation by Non-Fuel Renewables & Landfill Gas1.00
Offsite Electric Vehicle Charging2.113
Natural Gas1.10
Light, Medium & Heavy Fuel Oils1.10
Manufactured Ovoids1.20
Sod Peat1.10
Peat Briquettes1.10
Wood Chips (35% moisture)1.10
Wood Pellets1.10
Wood Briquettes / Logs1.10
District Heat Imported1.10
District Heat Exported1.10
Solar Thermal1.00
Road Diesel (DERV)1.10
Marked Diesel (marine use)1.10
Jet A1 Kerosene (Aviation)1.10
Aviation Gasoline (AVGAS)1.10

The system uses annual values for primary energy conversion factors from 2001 onwards – these are applied to the reported consumption from the relevant year.

The factors for all thermal and transport fuels have remained unchanged since 2001. However, the conversion factor for electricity has changed over time – as the efficiency of the electricity system has changed. The following is the time series of primary energy conversion factors used in the system for ‘Imported Electricity’.



SEAI has also prepared a forecast for the primary energy conversion factor for electricity out to 2020. The 2020 value is based on the assumption that Ireland meets its targets as set out in the National Energy Efficiency Action Plan (NEEAP) and in the National Renewable Energy Action Plan (NREEAP). It is also based on all of the macro and price assumptions inherent in SEAI’s Energy Forecasts for Ireland publication. The forecast value for the primary energy conversion factor will be reviewed periodically by SEAI.

The forecast and actual values for ‘Imported Electricity’ are:


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