Ground Source Heat Pumps
Ground source heat pumps (GSHPs) are a form of renewable energy that draws heat from the ground. They are fast growing in popularity thanks to their eco-friendly credentials and their earning potential. Geo Green Power has years of experience in the design and installation of domestic GSHPs and non-domestic GSHPs, please contact us today if you would like to learn more about a potential GSHP installation.
- What are the benefits of Ground Source Heat Pumps?
- Is a GSHP suitable for my property?
- How GSHPs can save you money
- How do I generate my returns?
- Renewable Heat Incentive
How Do GSHPs Work?
GSHPs work by extracting heating from the ground. A large loop of pipe, known as a ground loop is placed in the ground or through a body of water – the pump then circulates a mixture of water and antifreeze around this loop. Heat from the ground or water is absorbed into the fluid and then passes through a heat exchanger into the heat pump. The ground stays at a fairly constant temperature under the surface, this means that unlike some forms of renewable energy, heat pumps can be used throughout the year.
A key aspect of how GSHPs work is the physical size of the loop. The length of the loop depends on the size of the heat pump required and therefore the amount of heat required per annum. Longer loops can draw more heat from the ground, but need more space to be buried in.
It is typical for the loop to be laid flat or coiled in trenches just over a metre deep. If space is limited, a vertical borehole can be drilled instead, but if there is not enough space a vertical borehole can be dug to a depth of up to 100 metres. Heat pumps have some impact on the environment as they need electricity to run, but the heat they extract from the ground, the air, or water is constantly being renewed naturally.
Some property owners choose to combine their heat pump with a solar PV to gather the electricity needed for the pump. This would make the system entirely eco-friendly.
For more information on how GSHPs work, click here.
There are many great reasons to choose to have a GSHP installed under your property.
- They can lower your fuel bills – drawing heat from the ground means you will face cheaper energy bills as you will require less in electricity and gas to heat your property. This is especially true if you replace conventional electric or oil heating.
- Provide you with income – the government has set up a Renewable Heat Incentive Scheme (RHI) which can provide you with payments in return for the heat generated.
- Lower your carbon emissions – using less electricity means that you are reducing your carbon emissions and benefiting the environment.
- No fuel deliveries required – as you draw heat directly from the ground you will require no, or fewer, fuel deliveries.
- Minimal maintenance required – GSHPs are built to last and require very little in the way of maintenance.
GSHPs are more suited to some properties than others, so let’s take a look at some questions to establish whether it could be right for yours:
- Is your property suitable for a ground loop? It doesn't have to be particularly big, but the ground needs to be suitable for digging a trench or a borehole and accessible to digging machinery.
- What fuel will you be replacing? The system will pay for itself very quickly if it is replacing an electricity, oil, coal, or bottled gas heating system. Heat pumps may not be the best option for homes or businesses using mains gas but the return on investments can still be very good, for example, farmers using mains gas for drying processes.
- What type of heating system will you use? GSHPs can perform better with underfloor heating systems or warm air heating than with radiator-based systems because of the lower water temperatures required.
- Is the system intended for a new development? Combining the installation with other building work can reduce the cost of installing the system.
- Will the GSHP work with my existing radiators? Heat pumps can be used to power the majority of heating systems, but they work particularly efficiently when partnered with larger heating surfaces such as underfloor heating and radiators with large surface areas.
Ground source heat pumps can actually save you a great deal of money on your property. But how much you can save will depend on factors such as what kind of system you currently have, and what kind of pump you are replacing it with. The following factors influence the savings you can make:
- Your heat distribution system – underfloor heating can be more efficient than radiators because the water doesn't need to be so hot. If underfloor heating isn't possible, use the largest radiators you can.
- Your fuel costs – you will still have to pay fuel bills with a heat pump because they are powered by electricity, but you will save on the fuel you are replacing.
- Your old heating system – if your old heating system was inefficient, you are more likely to see lower running costs with a new heat pump.
- Water heating – if the heat pump is providing hot water then this could limit the overall efficiency. You might want to consider solar water heating to provide hot water in the summer and help maintain your heat pump efficiency.
|Existing System||Fuel Bill Savings|
1st April 2015 - 31st March 2016
1st March 2016 - 30th June 2016
|Carbon Dioxide Savings|
|Gas older (non-condensing)||£400 to £660||£2,555 to £3,955||£2,590 to £4,005||2,100 to 3,300 kg|
|Electric (old storage heaters)||£790 to £1,425||6,700 to 11,700 kg|
|Oil older (non-condensing)||£130 to £220||3,000 to 4,700 kg|
|LPG older (non-condensing)||£960 to £1,500||2,800 to 4,500 kg|
|Coal||£590 to £990||7,600 to 12,100 kg
Renewable heating systems provide an excellent return on investment. For every kWh of heat your system generates you’ll receive an RHI payment. This payment varies depending on the capacity of your system and the amount of heat you generate, however, the RHI is generous and based on these payments alone your scheme should provide a return on investment of approximately 15% per annum.
The heat is generated at a lower cost than heat sourced through conventional means such as mains gas, oil and electricity. Therefore, you’ll also see a significant reduction in your energy bills. On average a ground source heat pump will generate 4kWh of heat to every 1kWh or electricity used to power the pump, reducing your energy consumption and bills.
Overall taking into account the RHI payments and bill savings, a renewable heating scheme will provide a return on investment of approximately 15% per annum.
The Renewable Heat Incentive (RHI) cash payments are made quarterly. This can be across 7 or 20 years depending on the contract that you have entered into. The actual amount you will receive on various factors including:
- The technology you have installed
- The tariffs on the technology at the time
- Whether the installation is domestic or commercial
On the domestic RHI, Ofgem will pay you generous payments quarterly for seven years. Normally the heat required to heat the property will be deemed (estimated) and payments will be based on this amount. Renewable heat generated by heat pumps will be based on an estimate of the heat demand from an EPC combined with an estimate of the heat pump's efficiency.
The tariff is currently 20.46 p/kWh renewable heat; however, this is subject to change.
|Ground Source Heat Pump Applications||Tariff|
(p/kWh renewable heat)
|Application Submitted between 1st April 2018 and 1st April 2019 incl.)||20.89|
The commercial RHI provides a subsidy, payable for 20 years, to eligible, non-domestic renewable heat generators. This includes, for example, farms, businesses, hospitals and schools as well as district heating schemes such as where one boiler serves multiple homes. Eligible usage of the heat includes usage in an enclosed building for heating a space, heating water, or carrying out a process.
Payments for installations are calculated by multiplying the applicable tariff(s) by the amount of heat generated (using an RHI compliant heat meter) in the relevant quarterly period. There are two tariff tiers which apply to the commercial RHI. The tier 1 tariff is paid per kWh of heat produced up to 15% of full rated, annual capacity and the tier 2 tariff is paid on the remaining 85% of total heat output.
The current RHI payments for Commercial Ground Source Heat Pumps are currently:
|Tariff Name||Eligible Technology||Eligible Sizes||Tariffs|
|Water/Ground Source Heat Pumps||Ground Source Heat Pumps & Water Source Heat Pumps||All Capacities, Tier 1||9.09|
|All Capacities, Tier 2||2.71|
Once you are receiving RHI payments, the rate is index linked to CPI (Consumer Price Index). The RHI scheme uses a 'degression' system designed to manage the scheme budget available for the domestic RHI. From time to time, the tariff for a technology will be reduced (for new applicants only) if the total amount being claimed in total for that technology reaches a certain level. Anyone who is already claiming the RHI will not have their tariffs reduced through degression.
Contact Us Today
Overall, GSHPs can be a fantastic investment if your property is suited to them. If you would like to learn more about heat pumps or any other aspect of eco-friendly power, please get in contact with the team at Geo Green Power today. Our highly experienced staff will be happy to talk you through the process and provide any advice and insight you require.
A very professional installation. All the staff I met and dealt with were friendly and helpful. Would definitely recommend the Company. Thank you all, 5 stars!!
We found your service efficient and enquiries polite and considerate. I would definitely recommend your services to anyone who is looking for solar, in fact we have another farm building which will be sorted after Christmas, and would think we will be contacting you again. Thank you once again.
I have been very pleased with the speedy and efficient service we have received. Everyone in the Geo Green Power team has been pleasant to deal with and all aspects of the installation were carried out in a timely and effective manner. Many thanks for making our lives easier!