Heat pumps – a modern approach to renewable heating

5 May 2022

The government is encouraging homeowners to make the switch away from gas boilers to renewable heating appliances such as electric heat pumps to help lower our national carbon footprint.

At Alpha, we have been developing heat pumps for some time, and we know that heat pump systems work in a different way to gas boilers. So we always advise our customers that it’s important to know what to expect if you decide to adopt this technology in your home.

A heat pump takes low-temperature heat from a source such as the outdoor air and increases that heat. The heat can then be transferred to water that circulates around radiators or an underfloor heating system. The heat pump uses electricity to drive a compressor that raises the temperature of the heat source very efficiently – like your refrigerator, but in reverse.

As the UK is using more renewable sources such as wind to produce electricity, electric heat pumps are a good way to use this green energy in our homes and reduce our reliance on natural gas – a fossil fuel. The benefit for householders is reduced energy bills, as you won’t need to use gas for heating or hot water, and because heat pumps are so efficient – around 1 kilowatt of electricity can produce 3 kilowatts of heat.

The first thing to know when switching to a heat pump heating system is that it operates at lower temperatures than gas boilers. A traditional boiler-and-radiator system generally runs at around 70°C to 80°C; a heat pump system recommended temperature is between 35°C to 55°C.

This leads to the second important about a heat pump system. For the heat pump to work effectively, the house should be well insulated. Investing in loft insulation and modern windows and doors would be an important first step if your home does not have these already. You may also have to consider replacing older radiators with new, larger more efficient models to ensure that the system operates effectively.

Modern domestic heat pumps can also provide hot water for your home. To do this, you will need a hot water cylinder. If you already have one of these with your gas boiler system, it is likely that you will need to change this for a cylinder that is designed to work with a heat pump.

If you currently have a gas combi boiler, and therefore do not have a hot water cylinder (because your hot water is produced by the boiler as you require it), you will have to find a space for the hot water cylinder. This must be reasonably easy to access for installation and future maintenance.

A heat pump also has an outdoor unit which must be sited correctly. These outdoor units are generally around 1m x 1m x 330mm. If you have a garden or outside space, that can be an advantage, but there are units that can fit onto walls or balconies in apartment blocks.

The outdoor unit does not usually require Planning Permission (though it is best to check in your local area). And they are quiet when operating correctly. Noise levels are on average between 40 and 60 decibels (dB). For comparison, the Alpha E-Tec Plus combi boiler range operates at 52dB to 55dB; and a modern domestic fridge freezer sound levels are between 40dB and 45dB.

Although there are some differences in how a heat pump system will work in your home, it is worth considering them as an option. As the government is driving greater use of renewable energy, a heat pump could be an excellent way to future-proof your home, lower your own carbon footprint and reduce your energy bills.

Since heat pumps are electric, it’s also possible to combine them with solar panels (photovoltaics or PVs). Generating your own electricity from PVs on your roof, for example, means that you can reduce your use of power from the grid even further. Modern heat pump systems can be designed to work in tandem with PVs to ensure you make the most of ‘free’ energy from the sun.

Whatever your choice, Alpha can offer you advice on the best approach for your home to ensure that you’re adopting renewable technology in a way that works for you.