§ Mr. Clapham
To ask the Secretary of State for Trade and Industry what assessment he has made of the annual financial benefit to the average three-bedroomed household of using domestic gas for heating and hot water relative to other forms of heating. 
§ Mr. Battle
The Building Research Establishment estimate that during a year of average weather, based on average energy prices over the period 1996–1998, the typical costs of using different fuels for heating and hot water are as follows:
Estimated average annual energy consumption and costs for heating and hot water: 3 bedroom semi detached house, United Kingdom Fuel used Energy consumed 1 GJ Cost per year 2£ Difference compared to gas £ Difference compared to gas Percentage Gas3,4 100.5 452 — — Oil3 92.6 369 ?84 ?18 Solid fuel3,5 111.2 540 +88 +20 Electric off-peak6 67 630 +178 +39 Electric on-peak7 53.3 1,171 +719 +159 1 Energy consumed for domestic heating and hot water during a year of average weather (based on weather over last 20 years). It is assumed in the model that all of the house is heated so that the living area reaches a temperature of 21? C, with the following heating pattern: weekdays 2 hours in the morning, 7 hours in the evening. Weekends 16 hours. 2 Based on average fuel prices (including VAT) over the 3 years 1996–1998. Connection to mains electricity for other uses, such as appliances, has been assumed and the standing charge associated with this supply has therefore been excluded from the estimated costs. The figures reflect the overall efficiency of typical heating systems for each fuel (eg a standard gas or oil boiler with room thermostat or individual electric heaters with their own thermostats). More efficient systems are available for oil and gas, but not widely installed and they would obviously reduce energy consumption and the corresponding costs further. 3 Central heating and hot water. 4 Includes a standing charge for gas of £36 per year. 5 Based on anthracite used in closed room heaters and radiators. 6 Storage heating and hot water (dual immersion heater). The annual cost includes an additional standing charge for the off-peak tariff of £14 per year. 7 Heating and hot water.
Building Research Establishment Domestic Energy Model (BREDEM)
It should be noted that these estimates do not take account of all the factors that are relevant to such comparisons. For example, the lower capital costs of on-peak electricity installation can allow investment in higher insulation levels.