Rivers can provide renewable energy answers, says UTS


In London they are about to begin trialling technology that can draw carbon-free energy from the Thames, says the Underfloor Trade Store (UTS).

The water source heat pump is the first system of its kind and will provide hot water for nearly 150 homes, a 140-room hotel and a conference centre in south London. It is expected that the system will reduce carbon emissions from the Capital by 500 tons every year and reduce energy bills by 20 per cent.

It works by drawing water from two metres below the river’s surface where the temperature is sustained at 8 to 10°C at all times. The water is then filtered through a pump twice, removing the low-grade heat via a heat exchanger and returning the cooler water back into the river. After the heat has been transferred to a series of condensers, it is boosted to 45°C hot water using a process of reverse refrigeration. The water will then be piped to nearby homes.

The technology won Best New Product or Technology at the Climate Week Awards earlier this month, and it has been touted as revolutionary and ‘game-changing’ by energy secretary Ed Davey.

“I think this exemplifies that there are technological answers which will mean our reliance on gas in future decades can be reduced. Here you have over 100 homes, you have a hotel with nearly 200 bedrooms and a conference centre that won’t be using gas,” Mr Davey said.

“My department is exploring the potential for this sort of water-source heat pump across the UK, so we’re going to map the whole of the UK for the potential.”