Domestic hot water

The Energy Saving Trust (EST) commissioned BSRIA to conduct a major survey of hot water use in UK dwellings. The objectives of the project were to understand domestic hot water use, its temperature and the efficiency of its generation. This data could then be used to profile typical hot water generation and consumption in a UK dwelling, to help produce consumer guidance on energy efficiency measures and to inform government policy.

BSRIA installed and monitored the use of hot water in 120 dwellings across the UK. Specifically, we were asked to:

• measure each dwelling's overall consumption and the amount of energy used to produce it.
• measure the patterns of use, including the temperature the water is heated to
• measure the energy and volume used for individual draw-offs of water at different locations within a limited number of dwellings
• measure the total water (both hot and cold) use of the dwellings
• compare the measurements taken with assumptions made in the BRE Domestic Energy Model (BREDEM) for calculating energy use for domestic hot water