In It for Life: The Long-Term Savings and Sustainability Gains of Ground Source Heat Pumps
The new UK government has shown commitment to boosting renewable energy, lifting bans on new onshore wind turbines, and greenlighting solar farms.
However, more action is needed.
The Climate Change Committee (CCC) highlighted in its July 18th progress report to parliament that the UK will miss its target to cut emissions by 68% compared to 1990 levels without immediate intervention.
The CCC emphasised the importance of renewable energy, including ground source heat pumps (GSHPs), in reducing carbon emissions:
"The cost of key low-carbon technologies is falling, creating an opportunity for the UK to boost investment, reclaim global climate leadership and enhance energy security by accelerating take-up. British-based renewable energy is the cheapest and fastest way to reduce vulnerability to volatile global fossil fuel markets. The faster we get off fossil fuels, the more secure we become." - CCC, July 2024
Part of the solution to meeting the UK's 2030 and Net Zero targets involves increasing the use of heat pumps. Currently, only about 1% of UK homes are heated by this technology, but the CCC recommends that the figure must drastically increase to heat and cool 10% of our homes by that date. GSHPs, in particular, offer the lowest carbon footprint of any heating and cooling solution available.
This article explores the role of ground source heat pumps in decarbonisation, and also how they save energy users money.
Both of these benefits lie in an appreciation of the fact that the true carbon and monetary savings are revealed over time: that commitment to the technology pays back in the long term.
While the initial installation cost and embodied carbon are higher compared to other systems, their lower operational carbon emissions and high efficiency over their lifetime result in greater overall benefits.
Let’s explore what we mean.
Understanding the Cost Savings of Ground Source Heat Pumps
When considering GSHPs, it's essential to differentiate between the upfront cost and the total lifetime cost:
Upfront Cost: This includes the initial investment for installation, which can be higher than alternatives like Air Source Heat Pumps (ASHPs). It covers equipment, labour, and site preparation, such as test boreholes to assess energy potential.
Total Lifetime Cost: Over its lifespan, a GSHP offers significant savings due to lower operating and maintenance costs and higher energy efficiency. The ground loop itself is an infrastructure investment that can last over a hundred years.
Studies by Element Energy and Kensa Contracting highlight the economic benefits and efficiency of GSHPs, which achieve over 400% efficiency compared to 200% to 234% efficiency for ASHP.
GSHP systems' equipment, housed indoors, boasts a life expectancy of over 25 years, with total annualised costs approximately 25% lower in retrofit scenarios and 20% lower in new builds.
Investing in GSHPs means committing to a greener future with reliable, cost-effective heating and cooling. While it is true that GSHPs have a higher initial upfront cost, there are increasingly innovative ways to work around it - including council-led funding models as in our work for One Horton Heath.
Once complete, One Horton Heath will be the largest distributed ambient loop 5th-generation heat network / ground source heat pump system globally.
Counting Carbon Wins: Embodied vs. Operational Carbon
Understanding the carbon footprint of a product involves considering both its embodied carbon (the upfront environmental cost of manufacturing) and operational carbon (the emissions during its use).
For example, a car's total carbon footprint includes emissions from manufacturing—extracting raw materials, making parts, assembling, and transporting it—and its emissions while driving.
While GSHPs have a slightly higher embodied carbon compared to gas boilers and ASHPs (they are basically a larger and more complex technology), their operational carbon emissions are significantly lower over their lifetime. This results in a lower total carbon footprint.
Air Source Heat Pumps: Emit around 48% of the CO2 of gas boilers.
Ground Source Heat Pumps: Emit around 34% of the CO2 of gas boilers.
These figures are calculated over the 100-year lifetime of the ground loops, which often operate beyond this period.
GSHPs' lower operational carbon emissions more than compensate for their higher initial embodied carbon. In fact, the whole life cycle carbon is the true measure of ground source heat pumps’ success. Where the lifetime carbon of air source heat pumps (ASHP) is around half that of traditional gas boilers, the lifetime carbon of GSHP is lower still at around a third.
The CCC reports that direct greenhouse gas emissions from buildings contribute to 17% of the UK's total emissions, primarily from fossil fuels for heating and hot water. GSHPs, with their lower lifetime carbon emissions, are crucial to decarbonising heat. More on the technical aspects of GSHPs and how they can readily be used as a heating and cooling solution in most projects, can be found in our comprehensive guide.
Renewable Energy Now: The Urgent Need for Action
Preliminary data from the Copernicus Climate Change Service suggests that global temperature records were broken on successive days this summer, underscoring the urgent need to combat climate change.
“The hottest day record has been broken once again because the world continues to burn huge amounts of oil, gas, and coal. Every broken record is a warning that our climate is heating to dangerous levels. These warnings are becoming much more frequent; however, we have all the tools, technology and knowledge to stop things from getting worse – replace fossil fuels with renewable energy and get emissions down to net zero as quickly as possible." (Friederike Otto, Senior Lecturer in Climate Science at Grantham Institute, Imperial College London. Source, BBC News)
Heating accounts for around 37% of the UK's carbon emissions, with domestic homes contributing 13-14%. GSHPs, up to five times more efficient than gas, offer a low-carbon, cost-effective solution for heating and cooling buildings.
We must accelerate the adoption of heat pumps to transition to sustainable energy and meet our climate goals. Ground source heat pumps are essential in this mission, providing long-term savings and significant sustainability gains.
Join us in embracing a greener future with GSHPs: contact our designers to discuss how to adopt ground source renewable energy in your next large-scale project.