A comparison of the UK Standard Assessment Procedure and detailed simulation of solar energy systems for dwellings

Abstract

The drive to reduce worldwide carbon emissions that are directly associated with dwellings and to achieve a zero carbon home dictates that renewable energy technologies will have an increasingly large role in the built environment. The Standard Assessment Procedure (SAP), formulated by the Building Research Establishment (BRE), is the UK Government's approved methodology for assessing the energy ratings of dwellings. This article presents an evaluation of the advantage given to SAP ratings by the domestic installation of typical photovoltaic (PV) and solar domestic hot-water (SDHW) systems in the UK. Comparable PV and SDHW systems will also be simulated with more detailed modelling packages. Results suggest that calculation variances can exist between the SAP methodology and detailed simulation methods, especially for higher performance systems that deviate from the default efficiency parameters.

Keywords:

• Standard Assessment Procedure (SAP)
• PV
• solar domestic hot water (SDHW)
• PVSyst
• TRNSYS

Acknowledgements

The authors thank the BRE Trust for the funding and continued assistance of this research. Stewart Dalgarno, Director of Product Development, Stewart Milne Group and Andrew Lyle, Director, Renewable Devices Energy Solutions Ltd. were both helpful in providing details for the Sigma Home.