Following the major field trial of domestic heating pumps, the Energy Saving Trust has compiled a list of questions for everyone who’s considering using one in their household.

So here’s the first theoretical question about heating pumps and it’s the biggie: when should you consider using one?

The simple answer, is that the ideal candidate at the moment (bear in mind this is a new technology), is someone who lives in an existing property (or one about to be built) which is properly insulated and one off the gas network. Compared to other fuel types when gas is not available – coal, electricity, oil and LPG – heating pumps can reduce both energy costs and carbon emissions over the system’s lifetime.

Next question: when you get a heating pump, how do you get it to perform to its best capabilities?

First things first, make sure that your house is well insulated, up to the latest standards and recommendations. Basics are, good cavity and loft insulation, which should be both installed before the heat pump goes in. If you don’t have these in place, then forget this system; it won’t work to the level you need. Secondly, when it comes to the choice of ancillary systems, ensure that you choose low temperature under-floor heating, or radiators that are sized properly. Thirdly, get controls that you can understand and operate without confusion. If you install a system that you can’t control, or refine, then again, forget it, it will work poorly. In short, check that all the ancillary and support equipment is up to scratch.

Next question, For anyone that used to traditional heating systems, just what can you expect.

Don’t expect boiling hot radiators. When using a domestic heat pump system, the radiators will be warm, rather than hot. If radiators are used rather than a under-floor pipe system, then they will likely heat up more slowly. Expect also the pump to be working for longer periods than a conventional boiler. Some people also express the doubt that some systems will be able to cope with a large property’s needs in terms of heating and hot water, despite being specified properly. So it makes sense to install a secondary electric immersion heater.

Chief Scientific Adviser David Mackay, who’s at the Department of Energy and Climate Change, said:
“Heat pumps will be a crucial component of our low-carbon future, provided they perform well. It’s therefore essential to conduct trials to establish best practice, and perfect this technology for use in building throughout the UK.”

It is also essential that people fully understand not only how heating pumps work, but how they should be installed and used correctly.

Guest Article by Neil Camp

In the largest ever UK field trial of domestic heat pumps to date, it’s been concluded that whilst such installations can indeed result in carbon savings, more work has to be done to improve installation practices to ensure that the savings become an actual reality.

The field trial was commissioned by the Energy Saving Trust, the body that advises householders how to save energy and reduce their carbon emissions. They also provide advice to communities, local authorities, manufacturers and installers.

The key finding of the major study was that the industry has to improve the installation techniques for both air and ground source domestic heat pumps. If this happens, then there is a fair chance that they will become a mainstream technology for people; one that is consistent and quality in nature.

The field trial is split into a number of phases and the first has now been completed. It studied domestic heat pumps at some 83 sites. Four of these involved ground source systems; the remaining 29 centred on air source systems.

Lasting a full 12 months, the trial was started in early 2009 and involved a who’s who of the energy sector. These included: EDF Energy; NIE Energy; British Gas; Scottish Power Ltd; Scottish & Southern Energy plc; E.ON; RWE npower; The Scottish Government; The Department of Energy and Climate Change; The North West Regional Development Agency; Worcester Bosch; Baxi Group; Mitsubishi Electric; Danfoss UK
NIBE Energy Systems; and, Earth Energy Ltd.

Crucially, it was determined that the domestic heat pump installations operated at an overall efficiency rating of three and above. This effectively means that in return for every unit of electricity invested, the heat output was three times that, or more. This means that they performed very well in the tests.

The ground source heat pumps performed slightly better than the air source versions.

Now that the initial test has been completed, there are a number of key conclusions to be learnt.

Firstly, although they performed well, the heat pumps are sensitive to factors in their design, installation, commissioning and operation. Which makes the point that unless each part of the process is correctly carried out to high standards, then the heat pumps will not perform to expectations.

Secondly, the most simple systems performed the best. Those systems which were complicated, in terms of their design, or installation, were the systems which underperformed.

Thirdly, it remains unclear as to the impact of hot water production on the overall system. Heat pumps can deliver water at the appropriate temperatures, but it was not clear the effect this had on the system itself and more research is needed.
Fourthly, the controls for heat pump systems need to be installed correctly and then operated correctly. Controls are often misunderstood and used incorrectly.

Fifthly, where possible, the installation of heat pump systems should be the responsibility of one company, which would ensure a better after-sales service. Having a number of suppliers and installers work on system can be a recipe for later difficulties.

Finally, and perhaps not unsurprisingly, more study is needed into the domestic heat pump sector. The area is still in its infancy and far more background work is needed.

The Head of Business Development for the Energy Saving Trust, Mr Simon Green, said:
“We have a responsibility to make sure that customers’ investments are spent on measures that lead to the greatest potential to save carbon and reduce energy bills.

“This trial shows that when installed and operated correctly, heat pump technologies will save significant amounts of CO2 in the UK, when replacing oil or traditional electric heating.”

He went on to say that:
“Over its lifetime, a high performing heat pump installed today will save CO2 even when replacing gas condensing boilers due to the planned decarbonisation of the grid.

“But there is no doubt that the results are more varied than were expected, with results showing both high and low performing heat pumps.

“We are securing funding to extend the trial, with the objective of defining the reasons for variation in performance levels so that we can inform industry about good practice and advise householders on exactly what to look out for.”

The domestic heat pump sector may be in its infancy, but there is no doubt that it is beginning to make its prescence felt.

Guest Article by Neil Camp

As winter is upon us, Worcester is one of a number of boiler manufacturers who are offering advice on how to save money.

Worcester is part of the Worcester, Bosch Group and is a manufacturer of a wide range of gas boilers, oil-fired boilers and LPG boilers. In it’s combi boiler product range alone it has ten different models, all with a SEEBUK A rating of plus 90%.

Top of the five main tips from Worcester to help reduce home heating bills is lower your room thermostat to the lowest comfortable temperature. Bear in mind that by turning your thermostat down by just one degree, means you can cut fuel bills by around 10%.

Second tip is to remember that a number of key small measures, can collectively make a significant difference. Such moves as fitting low-energy light bulbs, washing clothes at low temperatures and turning appliances off rather, than leaving them on standby, are easy ways to reduce the amount of wasted home energy.

Tip three is don’t forget solar panels which don’t just need sunny weather to work. They are effective even in cloudy skies and provide useable energy; they can supply up to 60% of your annual hot water. Installation is not cheap, but starting at around £3,000, it needn’t break the bank and some homeowners could also receive a £400 government grant towards the cost.

Fourth tip is a new boiler. Much of course depends on the current boiler’s age and efficiency, but older models are simply not as efficient as more modern examples; a replacement condensing boiler can reduce a home’s carbon dioxide emissions by 15-30%.

It’s sobering to think that if everyone in the UK had a condensing boiler, the country’s annual carbon dioxide emissions would be reduced by 17.5 million tonnes. This would result in a saving of £1.3 billion on energy bills every year.

Last tip concerns the installation of heat pumps. A ground source heat pump, or an air source heat pump, can be used to harness the energy stored in the ground, or air, and meet a home’s heating and hot water needs. Heat pumps dramatically reduce fuel bills.

Government grants are available for the installation of such technology and costs vary from £1,500 to £2,000 for air to air systems, and between £7,000 and £12,000 for air to water.

Martyn Bridges, director of technical support at Worcester, Bosch Group said:
“Every year, millions of pounds worth of energy is needlessly wasted in our homes. With everyone watching their pennies more than ever, it has never been a better time to think about your home’s heating and hot water provision.

“Around 20% of the UK’s carbon dioxide emissions come from domestic heating systems. Householders can reduce these emissions and therefore fuel bills in a variety of ways, from small money saving measures to investing in renewable technologies.

“According to the Energy Saving Trust, each year every household in the UK creates six tonnes of carbon dioxide emissions. At Worcester, we are committed to developing environmentally friendly domestic heating systems designed to reduce the amount of energy that is wasted in the home, therefore minimising our impact on the environment.”

Guest Article by Neil Camp 

Comments from the Government’s new Chief Scientific Advisor have not gone down well with top boiler manufacturer Worcester.

They were dismayed by Professor’s David Mackay’s first public comments, on his first day in his new job as chief scientific adviser at the Department of Energy and Climate Change, which were designed to set out his vision for Britain’s energy future which centre on a significant increase in nuclear power capacity.

Worcester saw the advisor’s words as a: “…a thinly veiled attack on the use of gas in domestic heating.”

They were particularly irked at the Professor’s words which said:
“Setting fire to chemicals like gas should be made a thermodynamic crime. If people want heat they should be forced to get it from heat pumps. That would be a sensible piece of legislation.”

Neil Schofield, head of sustainable development at Worcester, Bosch Group, said:
“Professor Mackay’s comments set out a vision for Britain’s energy future based upon electricity, but it does not reflect the reality on the ground that domestic heat is predominantly gas powered in the UK. The logistics of replacing all gas-fired boilers with heat pumps, even in the medium term, would be an enormous undertaking significantly dwarfing the conversion from town gas to natural gas in the 1960s and 1970s.
“Professor Mackay has issued a new series of far flung objectives, bearing in mind that nuclear technology will take at least 20-30 years to come on stream, with no thought to the short term, the next 10 years. There is still no clear roadmap for either consumers or the heating industry of how we are going to meet the near term objectives.”
“Professor Mackay talks of people being forced to install heat pumps, but gives no indication of how consumers will be helped with the capital cost or what they should do if heat pump technology is not suitable for their own home. Our experience at Worcester, Bosch Group is that heat pump technology is not suitable for all applications. I would like to ask Professor Mackay how he heats his own house.”

Schofield makes it clear that he believes that the Professor’s comments are a further example of the Government and its advisers contradicting themselves in key policy areas.

He went on to say:
“On the one hand the Government is trying to encourage the uptake of renewable technologies with its proposals for the Feed-in Tariff for the Renewable Heat Incentive, but it is providing no upfront capital help for consumers to install the equipment and is now seriously considering taxing any monies generated. This will inevitably take away a major incentive for renewable technologies and make the Feed-in Tariff very unattractive to consumers.”

No doubt this rift between one of the country’s largest gas boiler manufacturers and a key Government advisor will play out over a long period of time.

Guest Article by Neil Camp