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How Efficient are Air Source Heat Pumps?
- From: Kevin Smith
- Published 21 October 2024
Being a renewable heating technology, Air Source Heat pumps (ASHPs) are becoming popular in the UK. They use less energy to heat water or provide warm air for a comfortable living in summer.
Moreover, with an efficient heating mechanism, these heat pumps take heat from the outside air even when it is cold. As a result, it reduces your energy bills and plays its vital role to minimize greenhouse gas emission.
That’s what we already know! But how efficient do air source heat pumps are? We will cover this here with some pros and cons. First, let’s know the working mechanism of this smart heating system.
Efficient Working Mechanism of Air Source Heat Pumps
Air source heat pumps extract thermal energy from the air that surrounds your house. Using a fan and refrigerant, they sufficiently utilize the heat even in low temperatures. The heat is then pumped into warm air before cooling it down to release it into its desired location.
In this case, the system seems to be operating backward relative to how a refrigerator would work. This is a very effective way of ensuring that one’s house is kept warm relative to old form heating systems. However, it is worth noting how they work at various temperatures.
Efficiency of Air Source Heat Pumps
Air source heat pumps are considered more efficient than gas burning boilers. They consume less energy and generate more heat. Generally speaking, gas powered pumps can heat 3 times for every 1 electrical unit consumed. Coefficient Of Performance (COP) is being referred to as 3 in this case.
Basically, the greater the COP, the more efficient the pump is. However, efficiency may be compromised once exposed to extremely low temperatures. These two realities are very different and should be appreciated even in the planning stages of the heat pump installation.
Efficiency of Air to Air Heat Pumps vs. Air to Water Heat Pumps
Heat pumps that transfer heat from outside air to water or air to air have several methods. Air to air heat pumps are perfect for areas without hot water heating since they send warm air straight into the house. They work well as air conditioners in moderate temperatures, but in really cold weather, they become less effective.
Conversely, air to water heat pumps warm water by using the heat that is extracted and then circulating it via underfloor heating or radiators. They may thus be used in households that need both space heating and hot water. They tend to have a higher Coefficient of Performance (COP), offering steady heating, especially in well-insulated homes. However, they may need a backup heat source during extreme cold. The choice between the two depends on home design, heating needs, and climate.
Parameter | Air to Air Heat Pump | Air to Water Heat Pump |
Heat Delivery | Warm air directly into living spaces | Hot water for radiators/underfloor heating |
Best for | Open-plan areas, homes without water heating needs | Homes needing central heating and hot water |
Cooling Capability | Can function as an air conditioner | No cooling capability |
Efficiency in Mild Temps | High efficiency | High efficiency |
Efficiency in Cold Temps | Lower efficiency, may struggle | More stable, but may need backup heat |
Coefficient of Performance (COP) | Around 2.5-3.5 | Around 3-4 |
Ideal Home Size | Small to medium-sized homes | Any home size including large properties |
Impact of Outside Temperature on Efficiency
Air source heat pumps do not do particularly well in extreme heat. They are more effective when the temperature outside is not at extremes. Efficiency drops when the refrigerating pump draws extremely cold air. In this case, a problem comes from the fact that the pump has to work harder to extract some heat from such air.
This makes it less efficient and more energy consuming as well. This is especially so in the UK winters whereby within the same season, temperatures differ in how well the heat pump performs. There is a need to factor this especially when intending to fit one within a domicile.
Cost of Running an Air Source Heat Pump
The cost of running an air source heat pump is the most efficient heat pump and depends on the occupancy of your apartment. But a well insulated flat will not waste much energy to maintain temperatures and save on costs.
In comparison, larger houses may use up more power because running costs may be high. Nevertheless, air source heat pumps can still be less expensive than the traditional heating systems. It is advisable to carry out the calculations of how much money you stand to save before making the purchase.
Benefits of Installing an Air Source Heat Pump
There are a plethora of advantages accompanying air source heat pumps such as cost effectiveness and mitigated greenhouse gas emissions. It is indeed a long term affordable solution. They are more eco-friendly than gas central heating systems as they exploit renewable energy sources from the surrounding air and use little greenhouse gas emissions.
Hence, this is a greener method of warming up your house. They however double as air conditioning systems during summer seasons where cooling is required in scorching months. Hence, they are also an all season solution.
Secure your Air Source Heat Pump Grant
If you or any of your household is on benefits, you may be eligible for air source heat pump grant.
Challenges of Using Air Source Heat Pumps
As much as air source heat pumps are effective, there are some drawbacks. One drawback would be the high upfront installation costs. Local authorities may offer subsidies that offset these installation costs. Also, they may tend to elevate very little heat when the temperatures are extremely low. This may result in the use of an auxiliary heat source in very frigid weather. This will also give you an idea if a heat pump will be effective in your house.
Maintenance Requirements for Air Source Heat Pumps
An air source heat pump’s efficiency also depends on how it is well maintained. Maintenance can be cleaning the filters and the outdoor unit itself. This maintains proper airflow and operation of the entire system. A qualified person needs to look at the heat pump once a year. In this way, it will be able to function as it is supposed to and heat your premises efficiently. Regular maintenance is also useful in prolonging the working capacity of the heat pump.
Consider Insulation Before Installing a Heat Pump
Optimal performance is possible from an air source heat pump, when proper insulation is adhered to. In case the house is poorly insulated, heat will dissipate resulting in more work from the pump. This leads to reduced efficiency and higher heating expenses.
Putting insulation on the walls, floors and even ceilings will help a lot. It assists in holding the warmth within a building thus making the heat pump effective. Otherwise, think about boosting the insulation of the house before putting it in place.
Noise Levels of Air Source Heat Pumps
You are probably aware that heat pumps, especially the outdoor unit, produce some amount of sound when in operation. This sound is as a result of two main components, fan and the compressor. Most of the heat pumps of today are purposely made silent.
But also the outdoor unit has to be placed strategically. For instance, it can be installed at a distance from bedroom windows to avoid noise disturbances. Such practical understanding enables you to be more thoughtful in the installation process and helps to ensure comfort to all the occupants of your house.
Government Grants for Air Source Heat Pumps
There are air source heat pump grants in the UK that are more directed towards the installation of heat pumps. Government initiatives in the form of the Boiler Upgrade Scheme (BUS) provide such support of up to £7,500 for installing ASHPs based on renewable heating systems.
These are of great help in reducing the overall capital outlay. It’s advised that you find out if such benefits can be granted to you prior to embarking on any work. This will help you cut down the cost on the installation as well as encourage the green initiative in your house.
Choosing the Right Size for Your Home
Choosing a heat pump With Air source heating systems is important to their efficiency. Too small a heat pump will not be able to effectively heat your household. Too large a heat pump, on the other hand, creates a situation where the unit will be on and off frequently which leads to energy wastage.
An expert installation can determine what sizes to install as your house needs. This way, the use of the heat pump remains optimal throughout the seasons ensuring that the temperature within the house is comfortable at all times.
Secure your Air Source Heat Pump Grant
If you or any of your household is on benefits, you may be eligible for air source heat pump grant.
The Bottomline
Air source heat pumps fully operate to the warmth of the home with great energy efficiency. They are green and provide cost benefits in the long run. Nevertheless, the reliability during harsh weather, running costs and investment made shall also be put in consideration. Proper insulation and proper sizing shall pave the way for improved efficiency. And with the government support in place, perhaps now is the right point in time to think about getting one installed. Be sure to consider the advantages as well as the concerns so as to know if an air source heat pump can be fitted in your house.
Frequently Asked Questions
The modern heat pump technology can take heat even from the cold air and compress it to increase its temperature and warm your home.
The installation cost can range from £7,000 to £13,000 in the UK. However, government grants like the ECO4 can cover the whole cost, making it more affordable to switch to a heat pump.
