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sustainable housing
15 Jul 2020

Sustainable heating for your home with an air source heat pump

By Oliver
  • Read time: 3 minutes
With energy efficiency becoming more and more of a forefront issue, air source heat pumps are an ideal solution to sustainable heating for most households in the UK.

Air source heat pumps are a cheap, efficient and above all renewable way of bringing warmth into your home. This system is available to anyone since it can be installed outside any exterior wall in any property. It functions by taking the heat out of the air and pumping it inside your home, even when it's freezing cold. This heating system will save you money compared to almost any other system while helping you to reduce your carbon footprint. This heat pump central heating system either comes as an air-to-water or an air-to-air system.

How does it work?

Air source heat pump heating works on the same principles as your fridge but in reverse. A liquid refrigerant that boils at very low temperatures is pumped back and forth between two heat exchangers. When exposed to outside temperatures, this liquid heats up and turns into a gas. By compressing this gas into a liquid, the temperature rises further. This warm liquid is carried to a heat exchanger which transfers the warmth to water which can be circulated through a central heating system. Finally, this domestic heat pump returns the liquid refrigerant to an expansion valve to reduce the pressure, decrease the temperature and begin the cycle again.

This is an incredibly efficient system. For every 1kWh of electricity that you supply to the system, you will typically receive 2 or 3 kWh of heat. This fluctuates throughout the year but it never stops being an efficient source of heat.

How ASHPs work

Which properties are suitable?

Heat pump efficiency is primarily determined by whether or not your property is on the gas grid. If it is, gas central heating is cheaper. If it is not, then an air source heat pump is a more economical choice than oil, electric, water, LPG or coal-powered heating.

The better insulated your home is, the better suited it is to an air source heat pump. Any steps you can take to improve the heat efficiency in your home reduces the requirements of the heat pump you would install. This is because a domestic heat pump works best when it can heat paces quickly and maintain the temperature with only a little energy expenditure.

In order to work optimally, heat pumps require the temperate difference between the pump and the heat distribution system to be as small as possible. This means that they produce heat at a lower temperature than other heating systems and that a larger area is needed for heat distribution. The best way to get the space required is to use underfloor heating or large radiators designed for heat pumps. Heat pump heating is also a more gradual process than that found in other systems. This means that air source heat pumps cannot make sudden and dramatic changes to a room's temperature.

The last thing people who are interested in purchasing an air source heat pump should bear in mind is that while the external unit is not very large, it must be positioned somewhere outside with enough airflow.

Potential savings

You may have heard of something called the Renewable Heat Incentive and asking, are air source heat pump classes as renewable energy? The good news is that they are. This means that once the newer system has been installed, you are eligible for payments that could range anywhere from £1,300 to £1,600 each year. Since the cost of a new air source heat pump can range from £12,000 to £15,000 the system quickly pays for itself (figures used are for estimation purposes only). This is on top of the savings you get from replacing a less efficient heating system.

You also get to save money on your monthly heating bill. If you are replacing a modern, A-rated gas boiler then you will likely save about £100 per month with an air source heat pump. If you have a less efficient, G-rated coal-powered system then you could be saving as much as £650 each month.

Tracking these savings and how much you are paying each month is also much easier with this kind of modern system. It is easy to integrate it into a smart home energy tracking system which will be able to tell you about your heat pump efficiency, how many kWh you have saved, how much money you have saved and more.

Savings also come in the form of low maintenance costs and long life expectancy. Air source heating systems will typically last for at least 20 years and during that time there will be little to no maintenance required. The system can be simply switched on and off as required, the temperate can be controlled remotely and set precisely with digital controls and you never have to worry about whether it is about to break down. All you need is a check every few years just to make sure everything is running as it should be.

LG ashp night

Choosing a better home heating solution

Anyone that has an older heating system stands to benefit from an air-source heat pump. They are not only better for the environment but they cost less to run than almost any other system, are among the most reliable and integrate seamlessly with other modern systems. It may sound strange to use the cold air from outside to heat your home but that is exactly what these systems do and they do it very well.


Written by Oliver

Oliver is a Content Specialist for 50five UK