Heat Pumps Explained
With the steady rise in energy prices and a global push toward environmentally friendly solutions, heat pumps are becoming an increasingly prominent alternative to current heating options.
Heat pumps utilise renewable thermal energy from the environment around us to provide heating but also cooling depending on your needs. It absorbs ambient thermal energy from the air, ground or water outside and transfers that heat to the inside of your home. Or it can work in reverse to transfer excess heat from inside your home and move it outside to produce a cooling effect in hot weather.
To find out more regarding heat pumps and the advantages they can provide, you can find out more by reading below.
How does the heat pump move heat from outside?
Heat pumps will always be able to extract heat energy from outside, even on a cold day. This is because it uses the hidden heat energy in the air otherwise known as latent energy. This renewable hidden heat energy can be harnessed by taking advantage of the process of a liquid being converted to a gas, or vice versa.
A heat pump will internally cycle a compound called refrigerant under varying pressure to induce the refrigerant to change state from a liquid to a gas and releasing heat in the process. This heat is then transferred into your home to provide heating on demand. The refrigerant is specially designed to change from a liquid to a gas very easily, which is why a heat pump can start the process even at very low outdoor temperatures.
A heat pump uses a process very much like the fridge in your kitchen – it extracts heat from inside the fridge and transfers it outside the fridge. This is the reason why the back of your fridge will feel warm as this is where the extracted heat is released so the inside of your fridge stays cool.
The different types of heat pumps
Depending on where the heat is extracted from, a heat pump can be either ground sourced, water sourced or air sourced. These will all draw heat from their respective sources; eg. Ground source absorb their heat energy exclusively from the ground. Looking at air source in particular, they can fall into two categories; air to air and air to water.
Air to water provides general heating and warm water using heated water pumped around a wet central heating system. This is usually via underfloor heating and specialised radiators.
Air-to-air can provide both heating and cooling by controlling airflow temperature in an interior space. It is this category that air conditioners fall into and can be controlled room to room.
Did you know?
Gas boilers are being phased out of new build UK homes from 2025 and from all UK households by 2035?
The pros and cons to heat pumps
Heat pumps come with many advantages over traditional gas powered central heating systems as they move rather than generate thermal energy, so they won’t contribute to rising global temperatures. They’re very efficient with the electricity they use too. For every single kilowatt of energy a heat pump consumes, it will create 3-4 kilowatts of renewable energy from the air. This means a heat pump is powered by up to 80% renewable energy captured from the air, with only 20% electricity is actually needed for it to operate, making it a truly eco friendly solution. Putting all this into perspective, this makes heat pumps approximately 400% efficient in direct comparison to a gas boiler that would peak at around 95% efficiency.
There are many, many positives to heat pumps, but they are not without some flaws, usually linked to their specific type. For example, ground source heat pumps require a large undisturbed area of ground to be installed and similarly water source heat pumps will require a large body of water as part of their installation. This will naturally require a lot of space and planning, although thankfully this is not an issue with air source heat pumps as they are less intrusive and more compact with only moderately sized outdoor units to position outside on the floor or wall.
Looking more specifically at air source heat pumps, air to water systems are somewhat slower at heating a home than a traditional gas boiler or air to air heat pump. This is primarily because the heat they produce needs to be transferred into the water as opposed to providing the heat directly through the air, adding an extra stage to the heating process. As a consequence, air to water source heat pumps will also provide heat at a lower temperature in comparison, as some heat will be lost in this process. Lastly, Air to air heat pumps such as air conditioning have few downsides and will provide energy efficient rapid cooling/heating effects at higher/lower temperatures but will not provide you with hot water.
Did you know?
According to the energy saving trust about 22% of the UK’s carbon emissions come from UK homes and about a third of that is from heating alone.
If you’re considering installing air conditioning and the benefits that come from these energy efficient heat pumps, we are here to help. Our friendly experts can guide you through the selection process and make sure your system is properly installed by our experienced team.