Energy savings from insulation improvements in electrically heated dwellings in the UK

Panel: Panel 2. Comfort and energy use in buildings

Authors:
George Henderson, Independent Energy Consultant
Dan Staniaszek, Energy Saving Trust
Brian Anderson, BRE
Mark Phillipson, BRE

Abstract

When the UK electricity industry was privatised over a decade ago, obligations were placed upon suppliers to improve energy efficiency. The resulting Energy Efficiency Standards of Performance (EESoP) have been in force since 1994, overseen by the industry regulatory body and funded through a special revenue allowance. This paper describes the results of monitoring to observe savings actually achieved as a result of the provision of insulation measures in electrically heated properties under the first two programmes, EESoP 1 and EESoP 2, covering the period up to March 2000.

Two different approaches were used. In EESoP1, an analysis of a sample of meter readings from 5% of dwellings before and after installation of measures was undertaken. In EESoP2, temperature and consumption monitoring of a smaller sample of dwellings was undertaken, including customer questionnaires to identify any external factors that may have influenced electricity consumption.

Analysis of meter readings from almost 8 000 dwellings in EESoP1 revealed a 12% saving in electricity consumption, corresponding to a reduction of 163 kg C per property in yearly CO2 emissions. Although large enough to be considered cost-effective, the savings were lower than expected. This has previously been attributed to a ‘comfort factor’, which assumed that savings were realised as higher indoor temperatures. The analysis described in this paper finds that the main reason for lower savings is that the homes monitored appear to be heated to a lower standard than assumed in the calculation of the savings, although a small rise in average indoor temperatures was observed after insulation.