Heat Pump: What are they and which should you choose?

With more people around the world becoming more conscious of global warming and their need to combat climate change, there is growing demand for eco-friendly alternatives to fossil fuels. Heat pumps are increasing in popularity in the UK because they offer an environmentally-friendly solution to heat homes and provide hot water, and save on electricity bills. In this guide, you can find out all you need to know: What are they? How much do they cost?

What is a heat pump?

A heat pump is a piece of equipment installed outside your home that can both heat and cool your house. In the colder months of the year, the heat pump pulls warm air inside your home to heat it up while in the summer months it acts in reverse and pushes the warm air outside so your home remains cool.

Heat pumps use a small amount of electricity but are considered to be clean because they do not burn any fossil fuels to heat or cool the home. They actually work very well in the UK climate because it enjoys a moderate climate - experiencing both cold and warm weather but not too extreme in each case.

How does a heat pump work?Heat pumps do not actually create heat themselves. In effect, they basically redistribute heat from the air or ground. They use a refrigerant that circulates between the indoor fan coil and the outdoor compressor to transfer the heat indoors or outdoors.

Heat pump system: What types are there?

There are two main types of heat pump: air source heat pumps and ground source heat pumps. In this section, we’ll look in more detail at the two of them and what are the differences.

Air source heat pumps

These are actually the most common heat pumps in the UK thanks to the climate we experience across our nation. The air source heat pump, or ASHP, essentially takes air from outside and converts it into heat that can be used to warm your home or heat up water tanks.

The unit sits outside the house and sucks the air in using a mechanism to compress and increase its temperature. ASHPs are relatively straightforward to install and do not require much construction work.

With the ASHP category, there are two types:

• Air to water systems: These are designed to send the heat generated to the water-based units of your house such as the hot water tank or radiators. They tend to be more effective with under floor heating rather than traditional radiators because heat is produced at a lower temperature than normal gas central heating.
• Air to air system: This is used for heating homes rather than water units. The flow of warm air generated by the pump is circulated via fans. The air to air system is slightly more limited than the air to water one as it is not designed to produce hot water.

Ground source heat pumps

The solar energy in the ground or the water can also be used to heat homes via ground source heat pumps. Also known as geothermal heat pumps, this type of heat pump involves laying pipes into the earth. While they are more complicated to install, ground source heat pumps are considered more reliable because the heat source underground is more stable and constant compared to air temperatures.

What about hybrid heat pumps?There are different combinations of hybrid heat pumps. Some involve a heat pump combined with a more traditional method of heating a home such as a gas boiler. Alternatively, you can have a mix of air and ground source heat pumps to heat your home in the most efficient way depending on the time of year

Heat pump UK: Installation and costs

Having explained about the types of heat pump on the market and how they work, in this section, we'll look more in detail at the costs and how to get one installed. While heat pumps will reduce the cost of your bills and your environmental impact over the long term, there is an expensive initial outlay to consider. It is important, therefore, to choose the best option for you.

Air source heat pump cost and ground source heat pump cost

Heat pump installation can be expensive so you should assess your options before buying. According to renewableenegyhub.co.uk, an air source heat pump costs in the region of £8,000 to £14,000 to install - and is one of the cheaper options. The exact amount depends on a number of factors including the size of the house and the amount of insulation

Ground source heat pumps are more expensive to install - according to Which.co.uk, they can cost between £13,000 and £20,000. While the initial outlay is more expensive and requires more work to install, the return on investment is considered to be good because you will have a low carbon heating solution that requires little maintenance.

For ground source heat pumps, there are a few issues to consider such as how much space you have available for pipes to be installed. You will need to have plenty of garden space, under which the pipes are installed. If you don’t have the space, ground source heat pumps can be installed vertically into the ground - although you will need permission to do this. While air source heat pumps are suitable for radiators, ground source heat pumps are more efficient if you have under floor heating in your home.

Are there government grants for installing heat pumps?Because heat pumps play a key part in reducing your carbon footprint and are beneficial for the environment, the UK government does offer grants for people wanting to install them. Currently, the Domestic Renewable Heat Incentive is the main scheme in place. However, this comes to an end on March 31, 2022, and will be replaced with a new Clean Heat Grant.

How to get the heat pump installed?

Before installing a heat pump you should always check if you need to apply for planning permission. To do this, you should contact your local council or planning authority. In the UK, most heat pump installations are considered ‘permitted developments’ meaning no planning permission is required. It is always best to check, however, to avoid problems further down the line.

You will also need to notify your electricity supplier about installing your heat pump to it can be connected to the network.

Bearing in mind there are a number of steps to follow and paperwork to carry out before installing a heat pump, the best way to go about it is by finding a heat pump installer. There are many companies around the UK that specialise in heat pump installation and will take care of the process for you. If you are unsure where to begin, a search online for ‘air source heat pump installers near me’ or ‘domestic heat pump installers near me’ will show you options in your area. Advice published by the Energy Savings Trust recommends you get a minimum of three quotes before deciding on which company to choose.

The advantages and disadvantages of heat pumps

As seen, the cost of installing a heat pump can be quite high, so it is worth looking at the pros and cons of heat pumps.

What are the advantages of a heat pump?

Some of the advantages include:

• They are cheaper to run than oil and gas boilers, meaning you can make savings on your bills;
• Heat pumps are do not rely on fossil fuels so by choosing one, you will be helping preserve the world’s natural resources, and reducing the impact of the greenhouse effect;
• They require less maintenance than traditional heating systems;
• Heat pumps have a long life span - up to 50 years. After the initial outlay, the combination of energy bill savings and maintenance costs mean they have a good long term return on investment;
• You can qualify for a Clean Energy Grant by installing a heat pump.

What are the disadvantages of a heat pump?

As with everything, it is important to look at the flip side. Some of the disadvantages of heat pumps are:

• High start-up costs and potentially tricky installation work if pipes need to be laid in the garden;
• While they do reduce your environmental impact, heat pumps do require electricity to run, meaning they will never be 100% carbon neutral;
• Some heat pumps experience more difficulty in cold climates, meaning they could be less efficient. In some cases, during very cold months, a back-up system, such as resorting to more traditional methods for heating, may be required.

Read more of our guides and advice for more information on what changes you can implement to help protect the environment.