St John’s College, Oxford and a new primary school in South Wales are among a growing number of educational establishments using ground source heat pumps to harness solar energy.

The 280-pupil Ynysowen Community Primary school, near Aberfan, and 500-student college are both utilising a heat exchanger, comprising a network of polyethylene pipes, buried under the ground to provide a means of transferring energy to or from the earth via a heat pump.

This technology was provided by Manchester energy technology firm ENER-G. The ground source system at St John’s College involves 48 boreholes and heat pumps with combined capacities of 146kW for heating and 115kW for cooling. It is projected to achieve carbon savings of approximately 17 tonnes per annum, the environmental equivalent of planting 1700 trees.

Ynsowen’s ground source heating system involves 14 boreholes and a total heat pump capacity of 74kW. Projected annual carbon savings of four tonnes are anticipated, which would equate to the environmental benefit of 400 trees.