Ground Source Heat Pumps vs Air Source Heat Pumps: Which is Ideal for Your Home?

When it comes to choosing energy-efficient heating and cooling systems for your home today, two solutions come to mind:

• Ground-source heat pumps (GSHPs)
• Air-source heat pumps (ASHPs)

Both systems are worth considering today because they can utilize renewable energy for heating and cooling. You can always rely on them to lower your carbon footprint. To choose between these two systems, you need to factor in the following:

• Climate
• Efficiency & Performance 
• Property size
• Your budget

As you read on, you’ll discover exactly how to make the right choice between GSHP and ASHP systems for your home.

Understanding how heat pumps work

Heat pumps work by extracting heat from outdoor air or the ground. After extraction, heat is further transferred into your home.

During the colder months, ground source heat pumps work by absorbing heat from the ground. The heat is further distributed into the indoor space through underfloor heating or hydronic radiators or fan coils for cooling. Air source heat pumps, on the other hand, work by extracting heat from the air and transferring it into your home using the same process. In the warmer months, however, the whole process is reversed for both systems.

Understanding the difference between GSHPs and ASHPs

The major difference between ground-source heat pumps and air-source heat pumps lies in their heat source. Ground source systems work by extracting heat from the ground’s stable temperature. Air source systems, on the other hand, draw heat from the outdoor air.

• GSHPs use underground pipes to extract heat from the earth’s ground. The good thing here is that underground temperatures often remain relatively stable year-round. This explains why GSHP systems are reliable for consistent and efficient heating.
• ASHPs extract heat from the outside air regardless of the temperatures. They’re typically placed outdoors for easy extraction of heat. Air source heat pumps also provide hydronic heating and cooling solutions just like ground source heat pumps. This is possible when the extracted heat passes through a water-based system before being circulated through hydronic radiators, hydronic cooling fan coils or hydronic underfloor heating system.

GSHPs vs ASHPs: Efficiency & Performance

For ground source heat pumps

• Efficiency: GSHPs are highly efficient. You can expect a Coefficient of Performance (COP) of 6-7. This means for every unit of electricity consumed, these systems produce 6-7 heat units when installed correctly. 
• Performance: The ground temperature is known to be constant. As such, GSHPs deliver reliable performance regardless of ambient weather conditions.
• Lifespan: With proper maintenance, you can expect your GSHP systems to last 50> years. However, the heat pump itself only lasts up to 20-25 years.
• Noise: GSHPs are very quiet, they are also located indoors in a dedicated plant room which further reduces their noise signature, this makes them an excellent choice for strict boundary noise requirements or architectural homes with requirements to hide all plant equipment. 

For air source heat pumps

• Efficiency: ASHPs are not as efficient as GSHPs. You can expect them to deliver a typical COP of 3-4. This value may even decrease during extremely cold or hot weather.
• In terms of performance, air-source heat pumps tend to perform best in milder climates. Their performance is never consistent during colder months.
• Lifespan: ASHPs’ lifespan falls between 10 to 15 years.
• Noise: ASHP’s are louder than GSHP’s, especially with lower tier brands, SóGeo can help recommend the right ASHP’s to suit your needs. 

GSHPs vs ASHPs: installation & costs

For ground source heat pumps

• In terms of installation, GSHP involves significant groundwork. Some of them include digging trenches and drilling boreholes. This makes the installation process complex and time-consuming.
• Due to excavation and loop pipe installation, it costs more to set up ground source heat pumps. The operating costs, however, are lower. This is simply due to the system’s high efficiency.

For air source heat pumps

• ASHPs are a lot easier and simpler to install than GSHPs. The entire setup should be completed within two to three days. 
• Furthermore, ASHPs are more affordable to set up. The only issue, however, is that their operating costs are slightly higher. This is due to the reduced efficiency of ASHPs during colder cold winter days or extremely hot weather when cooling.

Which heat pump is ideal for your home?

The choice of the right heat pump for your home depends on many factors, such as your budget, space, and performance needs.

• You should opt for GSHP systems if you have enough budget and space, and if you also need to lower your power consumption. You can rely on this system for consistent performance regardless of the climate.
• Air source heat pumps are recommended if you’re on a tight budget. You should also consider these systems if you lack enough space for ground installation.

Speak with experts at SóGeo today to get started with the setup of your heating and cooling system.