What is the energy performance coefficient?
The energy performance coefficient (EPC) is a dimensionless number that indicated the energy efficiency of a building. A lower EPC meant a more efficient building. In the Netherlands the EPC was the headline figure for new construction until 1 January 2021, when it was replaced by the NZEB / BENG indicators.
How was the EPC calculated?
The EPC was determined according to EN 15217 / NEN 7120. The calculation considered:
- Heating, hot water, cooling and ventilation
- Auxiliary energy — pumps, fans
- Lighting (non-residential only)
- Humidification (non-residential only)
- On-site renewable energy — PV, solar thermal
The calculated energy demand was normalised against the gross internal area and loss surface. The result: a number ranging from approximately 0.0 (energy neutral) to 2.0 (very inefficient).
Historical EPC requirements (NL example)
| Year | EPC requirement for housing |
|---|---|
| 1996 | 1.4 |
| 2000 | 1.0 |
| 2006 | 0.8 |
| 2011 | 0.6 |
| 2015 | 0.4 |
| 2020 | (transitional year) |
| 2021 | NZEB / BENG |
Replaced by NZEB
From 1 January 2021 three indicators apply instead of one EPC value (Dutch BENG framework):
- BENG 1 — maximum energy demand (kWh/m²/year) determined by insulation
- BENG 2 — maximum primary fossil energy use (kWh/m²/year)
- BENG 3 — minimum share of renewable energy (%)
Similar metrics exist in other EU countries to comply with the Energy Performance of Buildings Directive.
Applications
Although no longer used for new construction, the EPC still appears in:
- Existing-building dossiers — permits issued before 2021
- Comparison studies — to assess older designs
- Historical documentation — at sale or renovation
Related terms
- NZEB
- Energy label
- Energy-efficient home
- Net-zero energy
- Passive house
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