By Lucy Thompson

The Benefits to Using Water Source Heat Pumps

Using heat energy from the River Thames may not be the first method that springs to mind when thinking of ways to sustainably heat your home, but we did just that at our Riverbank Project.

While air and ground source heat pumps are a common theme in creating a more energy efficient home, the concept of water source heat pumps can often get overlooked. In this blog post we explain how these technologies work and how our Riverbank project harnesses the energy from the River Thames to supplement the heating demands of this state of the art home.

Image: The Greenage

How Heat Pumps work

Your standard home tends to burn fossil fuels in order to convert energy into heat – a gas boiler being a prime example. Heat pumps, on the other hand, don’t generate heat, they borrow existing heat energy from one source and transfer it to another.

In the case of air source heat pumps, outside air is blown over a network of tubes filled with refrigerant, which when heated turns from a liquid into a gas. This then passes through a compressor, increasing the pressure and into a heat exchanger which takes this heat and transfers it to the cooler air.

The refrigerant then condenses back into a cool liquid and the cycle begins again.

The difference between ground source and water source heat pumps

Ground source heat pumps work in a similar way: antifreeze flows around pipework buried in a shallow trench or deep into a bore hole, where heat from the ground is absorbed into the fluid. This then passes through a heat exchanger into a heat pump. The temperature of the fluid is raised by this process and then transferred to a hot water tank.

In the case of a water source heat pump, the same principles apply – but in this project we used the heat energy that exists in the river Thames! The technology works via a series of pipes filled with a refrigerant, submerged in the body of water.  The heat from the river is absorbed and delivered to the heat pump, which in turn heats up the hot water supply.

The benefits of a water source heat pump

The really great thing about water source heat pumps is that they are often more efficient than ground or air source heat pumps. This is because the temperature in a body of water such as The Thames tends to be higher on average and more stable throughout the year than the air or ground temperatures in winter.

Using the renewable heat naturally found in water can dramatically reduce the need for other energy sources to heat a house, providing on average 80% of the heating required year round with a minimal carbon footprint. They can also work well beside other heating systems, including other renewable sources such as solar panels.

Due to the system’s simple design, they require basic servicing similar to that of a conventional gas boiler, making them relatively inexpensive to run and maintain. Installation is also simpler, as unlike ground source pumps, WSHPs don’t require any deep boreholes or trenches. When compared to ground source and air source heat pumps, water source pumps have a longer lifetime, as well as being quieter to operate.

Contemporary riverside render

Designing a a sustainable, energy-efficient home 

Whichever system you choose to use, this technology is efficient because it delivers more heat energy than the electrical energy it consumes, making it more cost effective and releasing fewer carbon emissions than outdated heating systems utilising fossil fuels.

We are a holistic design studio providing Architectural, Interior Design and Landscape Design services throughout the CotswoldsLondon, SurreyOxfordshireBuckinghamshire and Berkshire.

If you have a project by a river or lake and would like to explore how we can help you harness that energy to heat your home, get in touch for an initial conversation.