If you’re thinking about switching to a heat pump, you’ve probably come across two main options - air source and ground source. Both can cut your heating bills and lower your carbon footprint, but they work in slightly different ways and suit different types of properties.
This guide covers how each type works, what you can expect to pay, how efficient they are, and which one could be the best match for your home.
Please note: Hive does not sell ground source heat pumps.
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How do they work?
Both air source and ground source heat pumps use electricity to move heat from outside into your home. The main difference is where they collect that heat.
Air source heat pump
An air source heat pump extracts warmth from the outside air and transfers it indoors to heat your home and water. It works a bit like a refrigerator in reverse, absorbing heat from the air through a refrigerant and using it to warm your central heating system.
There’s usable heat in the air even on chilly days, and modern air source heat pumps can keep working efficiently down to -25°C. They’re a reliable option for most homes, plus they’re compact, straightforward to install, and can connect to your existing radiators or underfloor heating without much hassle. There two main types of air source heat pumps are:
Air-to-water heat pumps:
These transfer heat from the air into water, which is then used to warm your central heating and hot water systems. This is the type offered by Hive, and it’s ideal for homes with radiators or underfloor heating.
Air-to-air heat pumps:
These transfer heat from the air directly into warm air, which is circulated around your home. They can also provide cooling in summer, but are less common in the UK and are not offered by Hive.
Ground source heat pump
A ground source heat pump draws heat from the ground instead of the air. It uses a series of underground pipes filled with a special fluid that picks up warmth from the soil, which stays at a steady temperature throughout the year.
That constant ground temperature makes ground source systems very efficient, but they require more space, either for horizontal pipe loops buried in trenches or vertical boreholes drilled deep into the ground.
Differences in efficiency
Efficiency is a big factor when choosing a heat pump. It affects both your running costs and your environmental impact.
Air source heat pump
Air source systems tend to be slightly less efficient than ground source ones because air temperatures fluctuate more than ground temperatures. Still, they can be far more efficient than a gas or oil boiler. According to the Energy Saving Trust, with a heat pump, for every unit of electricity you use, you can get three to four times as much heat (300 to 400%) in return. They work especially well in homes with good insulation or where heating needs aren’t too high.
Ground source heat pump
The ground stays at a steady temperature of around 10–12°C all year, which gives ground source heat pumps a clear advantage in colder months. When outdoor air temperatures drop below freezing, the soil beneath the surface remains much warmer, sometimes up to 15°C higher than the surrounding air.
This reliable warmth means the system doesn’t need to work overtime to heat your home and hot water. You’ll see more consistent electricity use, with fewer spikes in winter, and strong efficiency no matter the season.
Upfront price and running costs
When choosing a heating system, it’s helpful to know what to expect in terms of initial outlay and ongoing expenses.
Air source heat pump
Air source heat pumps are generally more affordable to install compared to other types, making them a popular choice for many homes. Ongoing running costs are typically low, especially if you’re replacing an older oil or gas boiler. Maintenance is straightforward and usually less expensive than looking after a ground source system.
Ground source heat pump
Ground source heat pumps tend to have higher upfront costs, mainly due to the additional work required to install underground pipes. However, once installed, day-to-day running costs remain low, and the system’s efficiency can lead to savings over time. It’s worth noting that it may take longer to recoup your initial investment compared to other options.
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Installation and planning
The installation process is quite different for each type of heat pump.
Air source heat pump
Installing an air source heat pump is usually straightforward. The outdoor unit gets mounted on a wall or set on the ground outside, and it’s connected to your heating system with some indoor plumbing. Most installations, like those from Hive, are wrapped up in about five days.
You typically won’t need planning permission, unless your home is listed or in a conservation area.
Ground source heat pump
Installing a ground source heat pump is a bigger job. It means digging trenches or drilling boreholes to put in the ground loops, which can take a week or longer depending on your property and the soil.
You might need planning permission, especially for deeper boreholes or if your home is in a protected area. Professional surveys are part of the process, and you’ll need to allow for more space and a bit more disruption while everything’s being set up.
Space and location requirements
Not every home is set up for both types of heat pumps, so it’s important to check what’s possible.
Air source heat pump
Air source units need clear airflow around them — typically about 1 metre of space on all sides, and are usually installed outside a kitchen, utility room, or garage wall. They’re compact, quiet, and easy to position, making them ideal for homes with limited outdoor space.
Ground source heat pump
Ground source systems need plenty of outdoor space, either for laying horizontal loops in trenches or for drilling boreholes. If your garden is on the smaller side, there might not be enough room for the pipework, and boreholes need specialist equipment and enough space to get the job done.
Because of this, ground source systems tend to work best for rural homes or properties with larger plots of land.
Air source vs ground source heat pump: which is right for my home?
Overall, both air and ground source heat pumps offer an efficient, low-carbon way to heat your home. The best choice comes down to your property and priorities, including cost, available space, and how each system performs through the seasons.
Start your heat pump journey today
If you want a straightforward, cost-effective installation with strong year-round performance, an air source heat pump is often the best fit. It delivers impressive efficiency, works in almost any home, and can be installed quickly with minimal disruption.
Our team can help you explore your options, assess your home, and find the right system for your needs.