Commission Decision of 21 December 2006 establishing harmonised efficiency reference values for separate production of electricity and heat in application of Directive 2004/8/EC of the European Parliament and of the Council (notified under document number C(2006) 6817) (Text with EEA relevance) (2007/74/EC) (repealed) (c. 74)

ANNEX IV Correction factors for avoided grid losses for the application of the harmonised efficiency reference values for separate production of electricity (referred to in Article 2(2))

Voltage:	For electricity exported to the grid	For electricity consumed on-site
> 200 kV	1	0,985
100-200 kV	0,985	0,965
50-100 kV	0,965	0,945
0,4-50 kV	0,945	0,925
< 0,4 kV	0,925	0,86

Example:

A 100 kW_el cogeneration unit with a reciprocating engine driven with natural gas generates electricity of 380 V. Of this electricity 85 % is used for own consumption and 15 % is fed into the grid. The plant was constructed in 1999. The annual ambient temperature is 15 ^oC (so no climatic correction is necessary).

According to Annex I of this Decision the harmonised efficiency reference value of 1999 for natural gas is 51,1 %. After the grid loss correction the resulting efficiency reference value for the separate production of electricity in this cogeneration unit would be (based on the weighted mean of the factors in this Annex):

Ref Eη = 51,1 % * (0,86 * 85 % + 0,925 * 15 %) = 44,4 %