narrowboatworld

It has been reported that heat pumps are being installed in many new canalside buildings, including the new visitor centre at the Falkirk Wheel, but what is less well known is that the technology really works, Chris Owen-Roberts writes.

The picture shows a frozen marina yet with warm buildings.

First challenge

Heat pumps were installed at Church Minshull Aqueduct Marina when it was constructed in the autumn of 2008, and this winter has been the first challenge to the system (and what a challenge!) since the marina opened in February 2009, with Robert Parton, Marina Director, remarking:

"We have not needed to supplement the heating of the building in any way this year so we are very pleased with the results. Even when there were several inches of ice on the water during the very cold weather and the outside temperature dropped to minus 15, the heat pumps kept the reception buildings warm. This saved a considerable amount of heating oil and the consequent carbon emissions."

Fridge in reverse

The heat pump extracts heat from the marina via submerged pipes. It works on the same principle as a fridge only in reverse, ie the ‘fridge' part is submerged in the water and heat is extracted from the water and concentrated in the output. By concentrating the heat, a large amount of low heat is changed to a small amount of higher heat.

The heat is then distributed through the building via pipes buried in the floor under the ceramic tiles. No additional heating is used and the temperature in the building didn't drop below 19 degrees Celsius throughout the extended period of hard frosts.

Virtually zero carbon

The system is virtually zero carbon as the only electricity it uses is to run the pumps. At Church Minshull Aqueduct Marina it heats the reception area, office, café and shop. The heat pump system is complemented by a roof-mounted solar heating array which provides all the hot water for the showers and washing facilities in the summer, again, with no additional heat supplementation.