Theprimary energy demand (according toEnEV) of a system includes, in addition to the actual energy demand of an energy carrier, the amount of energy required by upstream process chains outside the system boundary in the extraction, conversion and distribution of the energy carrier(primary energy). To determine the energy balance, the corresponding energy requirement is multiplied by aprimary energy factor, taking into account the energy carriers involved.
The primary energy demand is the main result of the energy demand calculation according to Directive 2002/91/EC (EPBD, Energy Efficiency Directive),which is used to calculateCO2 emissions as a factor in the environmental balance.
The value is particularly important when determining and assessing the heating energy requirement for buildings. The German Energy Saving Ordinance (EnEV), for example, sets upper limits for the primary energy requirement that must be adhered to when constructing a building
Primary energy factors, as defined in EN 15316Heating systems in buildings - Methods for calculating the energy requirements and performance levels of systems, are used for non-renewable energies.
This factor varies from region to region:In Germany, the Energy Saving Ordinance of 2007 with the last amendment in 2009 regulates the factor for electricity, for example, and otherwise refers to the standards DIN V 18599-1 and DIN 4701-10/A1
| Energy carrier | Primary energy factor EnEV | Minergie weighting factor[5] | SIA efficiency path | EN15603 AnnexE |
|---|---|---|---|---|
| Heating oil | 1.1 | 1.0 | 1.1 | 1.35 |
| Natural gas, liquefied petroleum gas | 1.1 | 1.0 | 1.36 | |
| Hard coal,Lignite | 1.1 and 1.2 respectively | 1.0 | 1.19 or 1.4 | |
| Wood(H) | 0.2 | 0.7 | 0.1 | 0.09 or 0.1 |
| Local andDistrict heating fromcogeneration | 0.0(W1)or 0.7(W2) | 0.6 | 0.9 | |
| Local and district heating fromheating plants | 0.1(W1)or 1.3(W2) | 1.0 | 0.9 | |
| Electricity | 2.6(S) | 2.0 | 2.9 | 3.14(S) |
| „Environmental energy“ (solar energy, ambient heat, etc.) | 0.0 |