Why Ground Source Heat Pumps (GSHPs) Are the Future of Heating and Cooling in the UK
Over the last few years one technology has been quietly revolutionising the way we heat our homes and businesses: Ground Source Heat Pumps (GSHPs).
Although solar panels and wind turbines often steal the spotlight in renewable energy discussions, GSHPs offer a powerful, efficient, and environmentally friendly alternative to traditional heating systems.
In the first blog from Onsen Energy, we'll explain how GSHPs work, explore why they are becoming a key player in the transition to sustainable energy, and explain how they help reduce our collective carbon footprint here in the UK—and save you money on your energy bills.
Let's go!
What Are Ground Source Heat Pumps?
Ground-source heat pumps are a form of renewable energy. They tap into the earth's stable temperature to provide heating and cooling.
The system works by circulating a mixture of water and antifreeze through a loop of pipes buried in the ground (known as a ground loop). By harnessing the natural warmth stored underground, GSHPs deliver energy-efficient heating in the winter and cooling in the summer.
Ground source heat pumps are suitable for domestic heating in a family home and are also implemented on much larger-scale projects.
How Do Ground Source Heat Pumps Work?
The heat from a GSHP is delivered into a building through a process that involves several stages:
1. Heat Extraction
As mentioned above, the GSHP system extracts heat from the ground by circulating a mixture of water and antifreeze through pipes in a ground loop. The fluid in the pipes absorbs the natural heat stored in the earth.
2. Heat Pump
Once the fluid carries the absorbed heat back to the building, it passes through the heat pump unit. This boils the refrigerant to create a gas, which the heat pump then compresses, dramatically increasing its temperature. This is where the temperature difference is amplified to make it suitable for heating the building. Installers like ourselves offer a complete ground source installation service—from drilling the boreholes to the headworks, where the system comes out of the ground, to installing the plant room.
3. Heat Distribution
The heat generated by the heat pump is then transferred into the building's heating system. This can be done in a few different ways:
- Underfloor Heating: In many installations, GSHPs are connected to an underfloor heating system, which spreads heat evenly across the floors, creating a comfortable indoor climate.
- Radiators: Alternatively, the heat can be delivered through traditional radiators. However, because GSHPs operate at lower temperatures than conventional boilers, larger radiators or more efficient designs are sometimes required.
- Air Handling Units: In some systems, heating and cooling are distributed via air handling units that blow warm or cool air into the building's rooms, similar to forced-air systems.
4. Hot Water Supply
GSHPs are also used to heat water for domestic use. Just like in a traditional heating system like a gas boiler, water is stored in a hot water cylinder and distributed through the plumbing system as normal.
What Does a Ground Source Heat Pump System Look Like?
The pipes needed for a GSHP system can be buried horizontally at a depth of 1-2 metres or in vertical boreholes between 50-300m.
The site's geology, heating, and cooling needs will determine the optimum system design. One way to confirm a site's thermal performance is to conduct a preliminary Thermal Response Test to ensure the GSHP system will operate as efficiently as possible.
Despite the need for groundworks, a professional drilling team will leave the site in as pristine condition as possible using specialist equipment, as we do here at Onsen, like state-of-the-art mud processing units, to avoid damage and reduce mess.
The Environmental Benefits of GSHPs
One of the most significant advantages of GSHPs is their minimal environmental impact. Unlike conventional heating systems that rely on fossil fuels, GSHPs utilise thermal energy from the sun stored in the ground, offering a sustainable solution that aligns with the UK's commitment to achieve net zero emissions by 2030.
GSHPs also reduce a building's energy consumption—and corresponding emissions—by up to 44% compared to air-source heat pumps and up to 72% compared to electric heating with standard air conditioning equipment.
GSHPs Energy Efficiency and Cost Savings
When it comes to energy efficiency, GSHPs outperform most traditional heating systems. The consistent underground temperatures allow GSHPs to operate at peak efficiency, even in colder climates. In fact, the countries in Europe with the most heat pumps per capita are also those with the coldest climates: in Norway, over 60% of households are heated with a GSHP.
While the initial installation cost of a GSHP system may be higher than that of conventional systems, the long-term savings often outweigh the upfront investment. Reduced energy consumption leads to lower utility bills, with a potential payback period of only 5-10 years.
As Kensa, the heat pump experts, state: "By delivering 3 to 4 times more heat energy than the consumed electricity to run the unit, a heat pump can reduce a property's heating costs by around two-thirds compared to direct electric heating."
GSHPs deliver up to an incredible 400% efficiency, compared to an efficiency of 90% for a modern condensing boiler.
Enhanced Comfort: A Superior Heating and Cooling Solution
Beyond sustainability and cost savings, GSHPs deliver exceptional comfort for a building's occupants. Unlike traditional systems that may produce uneven heating and cooling, GSHPs distribute temperature more evenly throughout a building through a system - like underfloor heating, as mentioned earlier.
The system operates quietly and eliminates the blasts of air associated with traditional HVAC systems, creating a more comfortable living or working environment.
Additionally, GSHPs' dual capability of heating and cooling allows for year-round climate control with a single system.
GSHPs: Durability and Low Maintenance
Another significant advantage of GSHPs is their longevity and low maintenance requirements.
The underground loop systems are incredibly durable, with a lifespan of over 50 years. The heat pumps themselves typically last 20-25 years, far outlasting traditional boilers.
With fewer moving parts and a more stable operating environment, GSHPs require less maintenance and are less prone to breakdowns, providing peace of mind and reducing long-term repair costs.
Why GSHPs Are the Future of Heating
GSHPs are a future-proof solution for heating and cooling. Their ability to drastically reduce energy consumption, lower greenhouse gas emissions, and provide cost savings makes them an attractive option for both residential and commercial projects.
With ongoing technological advancements in the sector, professional installers and decreasing installation costs, GSHPs are set to play a significant role in the transition to a greener, more energy-efficient future.
Whether you're a homeowner looking to reduce your carbon footprint or a business aiming to cut energy costs, GSHPs offer a sustainable and efficient solution.
Explore the possibilities of GSHPS and the thermal energy right beneath your feet: speak to our team about your project goals: gareth@onsenenergy.com
You can also sign up for our monthly mailer - Onsen On the Ground - for more insights and information on borehole drilling and ground source heat pump technology.