Electrical Building Services and the Energy Performance Certificate (EPC)

Electrical building services are essential to control the flow of electrical power throughout a building, required for Lighting, Small Power Heating, Ventilation and Air Conditioning (HVAC). The requirement for HVAC systems can be the greatest energy demand within a building.

Electrical systems comprise equipment (Main Switchgear, Transformer, Sub-Distribution and Final Distribution) whose purpose is to safely distribute the electrical power required in the building both to condition the environment and power the equipment used within the building.

Depending upon the individual building electrical power may be supplied at High Voltage or Low Voltage, electrical power is typically used within the building at Low Voltage. Depending upon the particular mix of electrical equipment within the building it may be necessay to provide additional equipment that corrects the power factor to be within acceptable limits.

The only specific element of the electrical building services that needs to be defined in respect of the Energy Performance Certificate is the definition of the overall building power factor. This must be specified from three pre-defined bands:

Less than 0.9
0.9 to 0.95
Better than 0.95

This definition is used to provide a % credit to the carbon dioxide calculations with a 1% credit for a power factor of 0.9 to 0.95 and a 2.5% credit for a power factor of better than 0.95.

Further information on electrical building services