Heat Pumps: Are they right for me?

With the cost of living still high, many people are looking for ways to reduce the running costs of their homes while contributing to the global journey to net zero. Here we look at how heat pumps may be an option for an efficient and environmentally friendly energy system.

We are all aware that there is a drive to meet net zero in the UK by 2050 and our media is full of stories about our changing environment. Combine that with a volatile economic situation globally, and stubbornly high energy prices, and many are looking towards alternative energy sources other than the traditional gas boiler for their homes.

There is often a lack of understanding about heat pumps and being an effective energy source. This overview aims to answer questions that might arise at the beginning of the decision-making process.

An introduction

In simple terms, heat pumps take air from outside a building and move it inside the house for heating and hot water.  There are two types: air source and ground source. The most common type in the UK is air source which, as its name suggests, takes the outside air and draws it across a heat exchanger to deliver heat indoors.

Ground source heat pumps use the temperature from underground as their source, which is more consistent than outside air temperatures.

The type of heat pump you go for depends on a range of factors, such as location, proximity to neighbouring properties, average air temperatures, property insulation and type of property. What is important to note, however, is that Government grants are available for both types and you can find out more by clicking here.

Predicting running costs

The most asked question is, how much will it cost to run? There is obviously an initial cost to installing a heat pump, so many people will want to understand how the system will save them money in the long run.

Unfortunately, there is no simple answer – each case will be different, but as a guide:

  • Potential energy savings are based on several variable factors, such as the type of system you currently use, your electricity tariff, what kind of heat pump you install based on your needs, your current heating systems and radiators, and your location.
  • For air source heat pumps, installers may supply what is called a CoP measurement, or Coefficient of Performance which calculates a figure which shows how much heat is produced for every unit of electricity used to produce it. In theory, the higher the figure, the more efficient the system.

However, be aware that this will fluctuate depending on how you use your heat pump and other external factors.

  • Seasonal Performance Factor can be more accurate as it shows data specific to your location like average temperatures and takes into consideration the size of radiators, specific heat pump design, among other factors. While no one can accurately predict the long-term cost savings with 100% accuracy, the SPF is a more reliable report to look at.
  • Annual variations in oil and LPG prices make it more difficult to predict any running costs and therefore potential savings, but your installer will be able to help you (with some limitations due to the uncertain nature of pricing).

Radiators or under-floor heating?

To get the most out of a heat pump system, it is important to maximise its efficiency by looking at other areas. Replacing gas boilers (as opposed to LPG or oil) can see energy bills increase, so it’s vital that the heat pump system is given the optimum operating support.

Because heat pumps deliver cooler water than boilers – typically 35-55°C – assessing your current heating system is important. A common misunderstanding is that you need to replace all your radiators with underfloor heating. What’s important is a larger surface area that can transmit more heat and overcome the lower temperature flow. Large radiators, either single, double or triple versions, can work just as well as underfloor heating.

A favoured combination is having underfloor heating in say the kitchen and/or lounge, with radiators in the rest of the house. If the radiators are of a decent size, a heat pump system will work well under these conditions.

Is hot water still hot?

For a heat pump to deliver and store hot water that can be used on demand, a hot water cylinder is required. The system can gradually heat water which is then stored. The temperature of the water within the cylinders must be high enough so that it can kill bacteria, so an immersion heater is often needed to keep the water up to the right temperature.

These systems are smaller than you might expect but you must consider usage in your planning. If you don’t have the space for a hot water cylinder, a hybrid system can be adopted, whereby electricity is generated by the heat pump, but the boiler still provides hot water. It is important to note that no Government grant is currently available for a hybrid system.

Maximising the system

As well as looking at your current radiators, underfloor heating and whether a heat pump will deliver all your hot water needs, maximising the effectiveness of a heat pump also means looking at whether you have sufficient insulation and draught excluding measures. The heat pump will operate at its lowest cost in a house that has adequate or good insulation. More insulation means less need for heat, which in turn means less demand on the heat pump and a more efficient system. In fact, a well-insulated house could be the difference between a larger or smaller heat pump, which also could mean a lower initial outlay.

Do you need planning permission?

Most heat pump installations don’t need planning permission, but do check with your local planning authority as there are exceptions notably in conservation areas or for listed buildings.

How to proceed

As with all major home improvement works, we would recommend getting three quotes from different suppliers and to use trusted, vetted installers. At HIES we have a network of experienced heat pump installers who are all vetted to the highest standards.

To find one in your local area, use the search tool here.