The overall aim of the project is to investigate the technical and commercial feasibility of a novel technology that would enable Ground Source Heat Pumps (GSHPs) powered by low carbon energy sources to become economically viable for a wide range of space heating applications.
It creates a new commercial opportunity for UK industry addressing fuel poverty by making space heating/cooling cheaper. In this project, the proposed EfficientGeoTech system avoids expensive, large drilling rigs required for conventional borehole, the use of portable piling machines allows GHEs to be installed on otherwise inaccessible sites.
What is the challenge?
UK's targets for CO2 reduction
Based on the 1990 level, the UK's targets for CO2 reduction is:
- 34% (increased from 26%) reduction by 2020
- 80% (increased from 60%) reduction by 2050.
In the UK, the sector of buildings accounts for about 40% of the total energy consumption, and almost half of the final energy consumed is in the form of heat. Its generation accounts for 47% of UK CO2 emissions. In order to achieve the national target to ensure that UK greenhouse gas emissions reduced by 34% by 2020 and 80% by 2050 (based on 1990 levels), clearly there is a need to substantially decarbonise the buildings sector. The aim is to largely replace the gas and oil boilers with low-carbon technologies by 2050.
In addition, the UK's aim for 15% renewables by 2020
DECC is encouraging Renewable Heat as part of the UK's commitment to aim for the very ambitious target of 15% renewables by 2020, and is introducing the Renewable Heat Incentive.
Renewable Heat currently satisfies only 1% of heat demand.
According to the USA Environmental Protection Agency (EPA), GSHP technology is the most energy-efficient, environmentally clean and cost-effective space conditioning system available.
The very high efficiency of heat pumps means that running costs are generally lower than other fuels off the mains gas grid e.g. oil, LPG, electric boilers and solid fuel.
Ground source heat pumps (GSHP) and air source heat pumps (ASHP) operate on the same principle like a fridge. The main advantage of ground source heat pumps over air source is that efficiencies are higher due to the fact that the depend on fairly constant temperature of the ground (>7m deep).
Heat pump system efficiency COP (Coefficient of Performance) and SPF (Seasonal Performance Factor) are strongly dependent on the temperature lift across the heat pump, i.e., the difference between the source and load temperatures (i.e., Tin,HP – TLoad) should be minimised.
The main benefit of a heat pump is that for every unit of electricity used to power the compressor, the heat pump will typically output 3-4 units of heat – making them 300-400% efficient. This compares to efficiencies of 85-95% for traditional heating systems.