The UK Department of Energy and Climate Change is promoting the use of large scale water source heat pumps providing heating and cooling to buildings from the water in rivers across the country. The Department says that about 40 urban rivers and estuaries in cities and towns across England could provide large-scale renewable heating supplies to local communities through water source heat pumps instead of traditional gas-fired or electric domestic heating.

The Department is limiting installations to try to ensure minimal impact on the riverine environment:

• The size of each installation is limited to 20 MW, equivalent to a heat pump of about 5500 tons capacity in the units often used for North American air conditioning. A 20MW heat pump could provide heating and hot water to about 8,000 to 10,000 UK homes.
• Installations must be at least 1 km apart.
• River temperature must not vary more than 2°C, for either heating or cooling.
• Water source heat pump locations are limited to areas where heat demand exceeds 5 -10kWh/m².
• Heat pumps should avoid environmental conditions where installation might be more difficult, e.g. salmonid areas.

The information, plus a link to a map of water source heating opportunities and, via the map page, to a context and rationale document, is available at https://www.gov.uk/government/news/regions-given-helping-hand-to-develop-locally-sourced-heat