Ground source heat pumps

What is a Ground Source Heat Pump?

A ground source heat pump extracts solar energy stored in the ground or and converts this to meet 100% of a building’s heating and hot water needs, all year round.

The electrically powered pump delivers three times more energy than it consumes, significantly reducing running costs. Typically, every 1kWh of energy a heat pump uses to power itself, generates 3kWh of heat.

Ground source heat pumps emit no point of use carbon emissions or air pollution, helping to significantly improve air quality and aid the UK’s ambition to achieve net zero carbon emissions by 2050.

Emissions from heat are the single biggest contributor to UK emissions

Heat innovation

Kensa Contracting has developed a ground source heat pump heating system that increases the cost savings to consumers whilst reducing the grid impact of electrification of heat. We have done this by combining ground source heat pumps with smart controls and dynamic energy pricing.

  • A new set of dynamic energy prices are released each day.
  • The smart control uses machine learning to create a model for heating the property based on occupant’s preference and building fabric.
  • Kensa’s heat optimisation programme combines the energy prices and heat model to create a heating schedule that balances comfort and cost.
  • The heating schedule is sent to the smart control.

Consumers benefit from clean, renewable heat with savings of up to 25% compared to a standard ground source heating system.

Dynamic tariffs

Dynamic electricity tariffs offer consumers cheap energy when electricity demand is low and renewable energy is plentiful and higher prices when demand peaks.

Octopus Energy’s Agile tariff, which we are recommending to ESO’s occupants, provides 48 half-hourly price points each day, allowing you to take advantage of this dynamic pricing.

Heat can account for over 50% of a property’s energy consumption and this means that large savings can be made by heating homes outside of peak periods. The Kensa heat optimisation programme automates this ‘load shifting’ so that consumers make savings from dynamic tariffs without having to change their behaviour.

How ground source heating works

A cold water/anti-freeze mix is pumped through the ground using a series of energy absorbing pipes. The anti-freeze mixture absorbs solar energy stored in the ground and is fed into a heat exchanger called an evaporator.

When the water anti-freeze mixture enters the evaporator, the energy absorbed from the ground is transferred to a refrigerant which begins to boil and turn into a gas.

This gas is fed into a compressor which increases pressure and makes the gas temperature rise. The hot refrigerant gas then flows into a second heat exchanger, called the condenser.

The condenser delivers water hot enough to provide heating and hot water for the building.

Having transferred its heat, the refrigerant gas reverts to a liquid. This liquid is then passed through an expansion valve at the end of the cycle to reduce its pressure and temperature, ready to begin the cycle all over again.

Express interest

Get involved

Download Kensa Contracting’s two-page guide about Energy Superhub Oxford, and find out how to get involved in this world-first project featuring ground source heat pumps, battery storage, electric vehicle charging points, and smart controls.

Project plan

ESO is a three-year project, launched in April 2019. 2020 is the key year for the project’s construction phase, and the system will go live at the end of the year.

The latest

15 September 2020

ESO in conversation: Matt Trewhella, Kensa Contracting

Energy Superhub Oxford aims to install low carbon heating at 300 properties in and around Oxford. We talked to Matt Trewhella, Managing Director of Kensa Contracting, about…

Read more

07 September 2020

Driving electric with DPD: the transformative power of electric delivery vans

27 August 2020

Green Light for Smart Renewable Heating Scheme in Oxford

26 August 2020

ESO in conversation: Tina Mould, Oxford City Council

Newsletter sign-up