BY KATIE - MYGREENPOD, 02 Apr '15

Tried and tested tech could be the answer for cheaper bills and a lower carbon footprint

The way we heat our homes is changing: as a nation, we’re on the lookout out for alternatives to fossil fuel heating that will help us meet the government’s legally binding carbon reduction target.

ecodan-4At the same time as reducing emissions by 80% (on 1990’s levels) by 2050, we all need to find sustainable, low-cost ways of keeping our houses warm and comfortable all year round. For most UK homes, gas boilers are a relatively cheap option, and the current price of oil is also helping those who aren’t connected to the gas network.

Still, only the hardiest of gamblers would bank on oil and gas prices remaining low for much longer; despite the recent drop, prices have increased significantly over the last decade.
If we rely on carbon-intensive gas and oil, our bills will be dictated by global fuel prices and there’ll be no certainty of supply; we now import more than we produce, making us much more reliant on supplies from Russia and elsewhere.

If you want to find a sustainable way to heat your home that could also reduce your monthly running costs, an air source heat pump could well be a better option.

Incentive payments

The government’s Domestic Renewable Heat Incentive (RHI) offers a regular financial payment for those making the switch to renewable heating in their homes. Like the Feed-in Tariff for electricity, the RHI offers financial rewards for those generating heat from renewable sources; the more efficient the renewable system you install, the more money you can claim.

The incentive is designed to offset the higher initial cost of renewable technologies in comparison with well-established carbon-intensive alternatives. It offers homeowners a quarterly payment which is guaranteed for seven years.

Air source heat pumps – and their ground source cousins – have already been confirmed as one of the options available to homeowners who want to cash in on the renewable potential of their houses.

Heat pumps: the basics

If the term ‘heat pump’ is putting you off, don’t let it: almost every home in Britain already has a heat pump sitting in its kitchen.

A heat pump uses the same technology as a refrigerator but in reverse. A fridge extracts the ‘heat’ from your food to keep it cool or frozen and rejects this heat out of the back where the copper ‘refrigerant’ piping is kept.

Along with the rest of the technology in your fridge, this copper piping uses what’s called a ‘vapour compression cycle’ to compress and expand the mixture of gases in the refrigerant. This means heat can be transferred from one area (the food) to another (the back of the fridge).

An ‘air source’ heat pump uses the same basic technology to extract low-grade heat from the outdoor air and upgrade it to the temperatures needed to keep your home and your hot water as warm as you need them.

Working with what you’ve got

‘Monobloc’ systems are the most straightforward air source heat pumps to use; they’re fitted outside the home and generally require single phase electricity and in/out water connections. They transfer the energy harvested from the outdoor air directly to an indoor water cylinder.

As a result these systems are pretty easy for a qualified heating engineer to install, and they can often work with existing heating infrastructures, such as radiators, as well as in hybrid situations alongside gas, oil and LPG heating. For RHI payments, both the heat pump and the installation need to be approved under the government’s Microgeneration Certification Scheme (MCS).

Heat pumps run on electricity, but they harvest renewable heat from the outdoor air – even in temperatures as low as -15°C. For every one unit of electricity consumed, even in the depths of winter, the home can receive an average of three or more units of heating.

It’s not a new idea…

Heat pumps have been used in areas like Scandinavia for decades and were even trialled in the UK in the 1980s. But it’s only over the last seven or eight years, following the introduction of inverter-driven technology by the commercial sector, that they’ve become a truly viable option for the majority of UK homes.

Heat pumps can now match the need of the house at any given time and maintain the temperatures required in the home without guzzling energy. This means heat pumps can deliver reliable heating and hot water in a sustainable way with low running costs, less maintenance and no need for gas safety certificates.

Heat pumps have already been installed in tens of thousands of homes throughout the UK, from the Isle of Wight to the Orkney Isles. The Pumping House is just one example of how heat pump technology can work in a restoration project.

Seal leaks first

Like any heating system, a heat pump works most effectively in properties with high levels of thermal efficiency, so the first question anyone considering a heat pump should ask themselves is whether they need to improve their home’s energy performance.

To qualify for the RHI, the government’s Green Deal Assessment insists that you undertake basic improvements, such as cavity wall insulation, loft insulation and double glazing, before installing a heat pump.

All credible heat pump manufacturers will also tell you that this is the first step you need to look at before forking out for a heat pump. Once you’ve dealt with any leaks in your walls, roof, windows and doors, a heat pump will almost certainly cut down your running costs – and could also significantly reduce your carbon footprint.

It doesn’t matter how old your property is as heat pumps are now being used in almost every type of building – from modern flats and new buildings to Victorian solid brick conversions and historic stone cottages. Whatever the home, as long as it achieves modern levels of insulation and thermal efficiency, there is almost certainly a heat pump to suit it.

Potential savings

There are so many variables that it’s impossible to say exactly how much you could save if you install a heat pump. The size of the property will affect the capacity you need (and therefore the cost of the unit) and the savings will depend on the efficiency of your current heating system.

Data from the Building Research Establishment (BRE), the UK’s leading centre for independent advice for the built environment, suggest that heat pumps can offer significant reductions in running costs compared with conventional fossil fuel systems and direct electric systems.

With its MCS-certified Ecodan range, Mitsubishi Electric is the market leader in air source heat pumps – and the company has developed an online heat pump selection tool to help offer an insight into potential savings.

Whether for a single house, a school, a hotel or an apartment block, the calculator has been designed to help you find the right solution by personalising the information for you. You just need to select the property type and then fill in information about its size, to understand the capacity you need, plus details such as the age of the building and its current heating system.

The calculator then estimates how much a heat pump could save in running costs and carbon emissions against gas, oil, LPG and direct electric heating, and illustrates what the RHI payments would be.

Fit for modern lifestyles

ecodan-5Modern systems like Ecodan offer advanced controls including wi-fi operation, automated weather compensation and intelligent room sensors. Together, these features fit well with modern lifestyles and make heat pump heating easier for homeowners.

Ecodan is also the only air source heat pump that’s been accredited by the Noise Abatement Society; its ‘Quiet Mark’ certification means you won’t notice it working away in the background.

Mitsubishi Electric has invested heavily in the R&D facilities at its Livingston manufacturing plant, focusing on homeowner experience, simplifying installation and making maintenance and monitoring even easier.

Remote energy monitoring now comes as standard on every Ecodan that leaves the factory, which Mitsubishi Electric sees as a key way of demonstrating the efficacy of heat pumps. The feature allows households to measure and maximise efficiency and minimise running costs.

To get a rough idea of the savings you could make by installing a heat pump, have a look at the calculator at ecodan.co.uk.