It’s now getting very close to the time when the UK will say a permanent goodbye to gas, at least as a mainstream fuel. This raises the question of what will be used to replace it. At present, the two main contenders are heat pumps and electric heating.
In this article, we’ve teamed up withRio Heatingas they share their insight and advice to help you decide which option is best for you.
How do heat pumps work?
Heat pumps can be thought of as reverse refrigerators. In fact, some heat pumps can function as cooling devices as well as heating ones.
Just as with refrigerators, the basic components of a heat pump include an evaporator, a compressor, a condenser, and an expansion valve.
In heating mode, the evaporator absorbs heat from the outside air, ground, or water and turns it into a gas. The compressor compresses this gas, which raises its temperature even further.
The heated gas then flows through the condenser, where it releases the heat into the indoor space. Finally, the expansion valve reduces the pressure of the refrigerant, and it returns to its liquid state and repeats the cycle.
Heat pumps that have a cooling mode just reverse this process. The heat pump absorbs heat from the indoor air and releases it to the outside. This cools the indoor space.
Heat pumps do require electricity to operate
Heat pumps are still pumps and as such, they need a source of energy themselves. This default energy source is electricity. How much energy the pump needs depends on how hard it needs to operate. This depends on how cold it is.
With that said, it’s important to note that most gas heating systems also need electricity to operate. They are likely to need less of it than heat pumps, but they will still go offline if there is no electricity at all.
It’s also worth noting that heat pumps are still likely to be a viable option for people who want to go fully off-grid. You would just need an on-site source of power. The sustainable options would be renewable ones such as solar panels and wind turbines. You could, however, use an old-school generator.
How does electric heating work?
This is a wide range of electric heating options, but they all work in essentially the same way. That is to say, they convert electrical energy into heat energy.
Electric heating elements, such as heating coils or ceramic plates, are used to generate heat. When an electric current passes through the heating element, it encounters resistance, which converts the electrical energy into heat energy. This process is known as Joule heating.
There also needs to be some mechanism to distribute the heat where it’s needed. When electric heating is used as the main heating system in a building, this tends to be radiation. Typically this is either via radiators or through an underfloor heating system (that works in much the same way as radiators).
Prerequisites for using a heat pump
Electric heating can be installed in just about any property, even an off-grid property. Heat pumps, by contrast, only work in certain situations. It’s therefore advisable to check whether your property is suitable for a heat pump before you start considering them as an option.
There are two key prerequisites to using any sort of heat pump. The first is space and the second is insulation.
Space
How much space you’ll need and where you’ll need it will depend on what type of heat pump you want to use. In the UK, currently, air-source heat pumps are the most popular option. This is probably because they’re the easiest to install.
Essentially, air source heat pumps look very similar to air conditioning units. They’re about the same size (on a like-for-like basis). They also have much the same requirements for installation locations.
Ground source heat pumps need to be dug into the ground. This obviously creates more work during installation. What’s more, the work will need to be repeated periodically for maintenance (albeit usually in intervals of several years). They also need a smaller unit to be installed inside the property.
Insulation
Heat pumps create a steady flow of heat. Unfortunately, they do not (yet) create nearly enough heat to outweigh a lack of effective insulation. The need for top-notch insulation is probably the single, biggest reason that heat pumps cannot be used as the only source of heating for older properties.
In principle, you could deal with this by having an additional source of heating. In practice, however, this could be more hassle than it’s worth. The main reason for this is that you would almost certainly need different radiators for the different heating systems.
Theoretically, you might be able to resolve this by using freestanding electric radiators to boost your heating as needed. In practice, however, if a heat pump isn’t likely to work as your main heating, it’s probably more sensible just to install electric heating in the first place.
Comparison of heat pumps and electric heating
If you can choose between heat pumps and electric heating, here are the points you should consider.
Cost-effectiveness
The initial installation cost of a heat pump tends to be higher than that of an electric heating system. Over the long term, however, this is outweighed by the lower running costs.
Energy efficiency
Heat pumps have better energy efficiency than electric heating. This is because heat pumps essentially just move existing heat from one location (e.g., the air) to another (e.g., your home). Electric heaters actually have to convert electrical power into heat.
Maintenance
The maintenance requirements of heat pumps tend to depend on the type of pump used. Air source heat pumps are exposed to the weather (and wildlife). They, therefore, tend to need regular maintenance. By contrast, ground-source heat pumps are much more protected. This means they usually need lower maintenance. Electric heating requires even less maintenance.
Suitability for the UK’s climate
Modern heat pumps can work in conditions that are well below freezing. Having said that, as temperatures drop, so does their operating efficiency. This means that, currently, they tend to work best in areas where the temperature rarely drops much below freezing. Realistically, this covers most of the UK.
Sustainability
Heat pumps are more sustainable than electric heating systems. This is purely because all electricity generation has an environmental price. The price is lower when renewables are used but even renewables have their issues. Heat pumps use less electricity than electric heating systems and are therefore the more sustainable option.
