Frequently Asked Questions
Here is a comprehensive list of people’s most common queries concerning heat pumps, solar heating, renewables, and the services that we provide. If you can’t find the answer you want, get in touch with one of our experts direct.
Heat Pumps
- Why don’t we hear more about heat pumps in the UK? Are they new?
- The use of heat pumps is common in the USA and several parts of Europe. They were actually invented more than 50 years ago, and continuous development has greatly improved their efficiency and reliability. They are now a proven, cost-effective, safe and environmentally friendly alternative to fossil fuels. With the increasing interest in renewable energy and rising fuel costs, heat pumps are becoming increasingly popular in the UK.
- How efficient is a heat pump system?
- Ecovision heat pumps are very energy efficient. The Coefficient of Performance (COP) is a term used to measure the efficiency of a heat pump. This is the ratio of heat delivered by the heat pump in relation to the electricity required to generate the heat. A typical COP for our heat pumps would be 4, meaning 1kW of electricity is required to produce 4kW of heat.
- How does the efficiency of ground source heat pumps and air source heat pumps compare?
- The COP of air source heat pumps is typically lower than ground source systems. Whilst air source heat pumps are designed to achieve an average COP of 3.5 to 4.0 in the UK climate, ground source heat pumps can achieve a COP of over 4.
- How large are these heat pump units?
- A typical heat pump unit for a domestic dwelling is about the same size as a fridge/freezer.
- How noisy are heat pumps?
- Ecovision heat pumps are very quiet with noise levels equivalent to that of a fridge. They should ideally be sited in a separate plant room or utility room, or at the back of a garage.
- Can the systems provide cooling?
- Yes, some of our systems can provide additional cooling, utilising the lower temperature of the ground on warm days to extract heat from the house. There are also reversible models in the range able to provide ‘dynamic’ cooling.
- Why is underfloor heating preferred with heat pumps?
- Heat pump systems are ideally matched to modern low temperature underfloor heating. Standard radiators operate with water temperatures of 60°C to 70°C. Underfloor heating can operate at temperatures as low as 30°C. Heat pumps are far more efficient when operating at these lower temperatures.
- Will a heat pump work with radiators?
- Radiators can be connected to heat pumps very effectively but are less efficient than underfloor heating. This is because radiators require a higher flow temperature which will cost more to run. Our consultants will be able to advise on the suitability of radiators in your property, as well as give details on more efficient radiator systems that are available on the market.
- Can I use a standard domestic electricity supply to power my heat pump?
- Yes. We have a range of heat pumps which have been specifically designed to run on a standard UK single phase supply. However, a three-phase supply is essential for some of our larger units.
- I am currently designing a new house which will be extremely well insulated. Would a heat pump system be worth considering?
- Yes, definitely. New houses are ideally suited to heat pumps due to the improved levels of insulation that they provide. All UK new builds must meet and exceed Building Regulations which set mandatory standards on reducing heat losses and improving energy efficiency. The better the insulation, the greater performance standards and efficiency that a heat pump will be able to provide.
- I have an older style property. Can I still fit a heat pump system?
- Yes, you can, but it may be cost prohibitive to install a heat pump in an existing property where insulation is not that good. The cost of a system is directly related to its size and with heat losses being fairly high from older buildings, this can add substantially to the capital cost of installation. Money spent on upgrading insulation levels can save a considerable amount on the capital cost. As part of our estimate process, we will be able to advise you as to whether a heat pump will be a cost-effective solution for your property.
- What size heat pump do I need?
- The heat pump is sized to meet the full space heating losses from your building. The better insulated your house, the smaller the heat pump you will require - and the less money it will cost. It may prove cost effective for you to improve the insulation of your building and have a smaller heat pump system. In order to make an accurate calculation of the heat pump you need, you will need to ask your building service professional (builder, architect etc.) what the heat losses are for your home. Alternatively, Ecovision can work out these calculations for you.
- Who can install heat pumps?
- For reasons of quality assurance our systems can only be installed by our own qualified and experienced engineers. Other installation work, such as the digging of the trenches and groundwork, can be organised by yourself with our assistance.
- How big are the trenches for ground source heat pumps?
- The amount of trenches and ground collectors required is dependent on the size of the system. For dimensioning the required installation area, the following rule of thumb applies: heating capacity of the heat pump (kW) x 10m. The individual pipes should be buried at a depth of about 1 to 2 metres and spaced about 0.6 – 0.8m apart.
- My land is not suitable/too small to dig trenches - can I still fit a heat pump system?
- If you do not have a suitable area for trenches, boreholes can be used for the ground collectors, although this may be more expensive. An air source heat pump is also an excellent solution where ground is unsuitable for digging or is too small. With no digging, borehole or slinky requirement, air source heat pumps can provide significant installation cost benefits over ground source systems.
- Can I install trenches on a downward sloping site?
- Yes, provided you can physically dig the trenches, a moderate downward slope is not a problem. Consideration needs to be given to purging air from a system with ground loops higher than the heat pump.
- I have some very wet land. Can I use this for my ground source heat pump?
- Yes, wet land is better at conducting heat so, as long as you can physically dig a trench, it’s ideal. It is also possible to use large ponds and fast flowing streams as an energy source. Please speak to our consultants for more details.
- What are the environmental and energy efficiency benefits of Ecovision heat pumps?
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Heat pumps are one of the lowest-carbon emission methods of heating any building. Unlike boilers, there is no pollution on-site. As the electricity grid gets cleaner, and more renewable electricity is brought on line, so the carbon emissions from the heat pumps will fall.
Most electricity suppliers are now offering ‘clean green’ electricity from a renewable energy source and, if you use this to power your heat pump, your property will be totally heated from renewable energy with zero carbon emissions.
Heat pumps have no flammable fuels or tanks; no flue, no pilot light and no toxic exhaust gases. There is also no additional pollution from LPG or oil tanker deliveries.
A heat pump can last up to five times longer than a new boiler and as the essential ingredients are copper and steel, the comparable embodied energy is very, very low..
- What is the design life of Ecovision heat pumps, and the collector coils?
- Ecovision heat pumps have a design life of 25 years. The collector coils buried under ground have a design life of 100 years - the same as the gas and water main buried in the road.
- What about the servicing and maintenance of heat pumps?
- There is no need for regular servicing or annual safety checks and maintenance is very low. All our systems come with a 1-year parts and labour warranty. Extended warranties are also available on request.
- How do running costs compare with conventional alternatives?
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It depends what you are comparing. In a modern, well insulated house, a heat pump can offer very high efficiency and moderate running costs. A conventional oil boiler would cost considerably more to run, and electric heating would be at least three times as expensive.
It is true that the very best of the modern condensing gas boilers may only be a little more expensive to run but that is on current gas prices, which continue to rise. Also, all fossil fuel boilers need regular servicing and maintenance.
- Are there any grants available?
- Take a look at our grants page to see up to date information on grants and other funding. We will be happy to assist you in applications for grants.
- What about VAT?
- VAT is charged at 5% for domestic heat pumps installed in the UK. Ecovision will invoice third-party installers or builders at 17.5%, and they should invoice the homeowner at 5% if they are registered for VAT.
- I am sure my project is well suited to one of your systems. What do I do now?
- Just write, email or call us using the details provided at the bottom of this page or our contact page. The easiest way to set your system design in motion is to complete our Project Information Form which can also be found on our contact page. From this we will be able to estimate the suitability and probable size of a heat pump system and provide you with outline costs. Typical delivery times are about 2-3 weeks for the ground loops and 4-5 weeks for the matching heat pump.
- Where can I find further information on heat pumps and renewable technologies?
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For further information on heat pumps, as well as other renewable technologies and energy efficiency measures, the following organisations will assist:
- If the temperature drops below zero will my air source heat pump work?
- No problem. Our air source systems can operate efficiently down to temperatures as low as -20oC.
Solar Hot Water Heating
- How effective is solar water heating in the UK?
- Solar water heating is now very efficient. About 4m2 of good quality panels on a roof should provide the average family with around 50-60% of their hot water needs spread throughout the year (100% on good sunny days, 10% on gloomy days).
- Is there a difference in the effectiveness of solar panels for different parts of the UK?
- The solar radiation received on a collector facing due south at an incline of 30o varies from approximately 900 kWh/m3 per year in Scotland and the North of England, to approximately 1,300 kWh/m3 per year in the South West.
- What use are solar heating systems when the sun is not shining?
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Over half the energy falling in the UK is in the form of diffuse sunlight. On a cloudy day when there is little or no direct sunlight there may be 300W/m3 of diffuse light falling on a flat horizontal surface. This is sufficiently intense to be usefully collected by specially-designed solar collectors.
Whilst the highest amounts of monthly solar radiation are obviously experienced in the summer months, there is enough radiation coming from the sun in spring, autumn and winter to make a very useful contribution to a household’s energy needs. A properly sized system can be expected to provide the following:
- 80 – 90% of all summer hot water needs.
- 40 – 50% of spring and autumn hot water needs.
- 10 – 15% of winter hot water needs.
- Why do I need to have a back-up system in place to support my solar heating system?
- The times of highest demand do not necessarily match the times of maximum solar gain – or sunshine. For example, the peak demands for space heating occur when it is cold and dark, when there is little or no sunlight, Some form of storage or back-up supply must therefore be incorporated into most systems.
- How much would a typical system cost?
- Cost depends on the number of panels required, the size of the cylinder and on installation details such as accessibility for the scaffold and the complexity of the wiring. A typical system will cost around £2,000-£3,000 and a government grant of £400 is available to assist you.
- How should solar panels be fitted for maximum efficiency?
- For maximum efficiency, solar panels should be mounted on a south facing roof at a 30o angle with the horizontal and away from trees, surrounding buildings and chimneys. Fortunately, the average tilt of a UK house roof is about the optimum for receiving solar energy in the UK.
- Why are solar collectors not designed to collect as much light as possible to convert to heat?
- Collectors are designed not to collect as much light as possible as this would only overheat the system. Hot water usage and storage capacity is finite and the way in which people use hot water, and the times at which they use it will vary from day to day and have to be taken into account.
- What about the aesthetics of solar collectors?
- The effect that solar collectors will have on the aesthetics of a building is really a matter of personal taste. Some people like an array of futuristic looking tubes on the roof whereas others prefer the flexibility that panels bring. Panels can be integrated into roof tiles which makes them look more pleasing and fits in better with architectural designs. By integrating panels into new buildings, significant savings can be made on roofing materials that would otherwise be incurred.
- Which system is most popular, evacuated tubes or flat plate collectors?
- In Germany, where both types of solar systems have been used for over twenty years, the market originally favoured evacuated tubes and flat plate panels were considered as second best. Today vacuum tubes comprise only 18% of the market, with flat plate panels taking a massive 82%. The end users find panels just as efficient, more aesthetically pleasing but also longer lasting with fewer faults and service calls required.
- I have only limited south facing roof space – which panels are best?
- Evacuated tubes perform slightly better than flat plate collectors in relation to their size. Generally a vacuum installation needs around 10-12% less roof space than an equivalent flat plate system.
- What if my roof faces south-west or south-east – will solar collectors still be effective?
- Ideally the solar panels should be oriented to face south. However, they will work with only a slight loss of efficiency sited between 30 degrees east and 40 degrees west of south.
- How long do solar water heating systems take to install?
- Time needed for installation will depend on the size and complexity of the job. However, most systems usually take 2-3 days to install.
- What servicing and maintenance do solar collectors require?
- Installations with vacuum tubes usually require more service calls than installations with panels owing to the more fragile construction of tubes. Tubes can experience stress fractures caused by the expansion and contraction of the glass in tube systems which means that the vacuum fails. The whole of the heat systems in flat plate panels is made of metal; glass covers the absorber plate but rests on a washer which allows differentials in expansion and contraction. Well engineered flat plate panels are much more robust than tube systems.
- What financial incentives are there for me to install a solar heating system?
- The Low Carbon Building Programme funded by the Government offers homeowners up to £400 to assist with installing a solar energy system. What’s more, a system that is installed by a heating professional attracts VAT at 5%.
- Is planning permission required?
- Planning permission is not generally required for the installation of solar panels. However, it is always worth checking with your local planning authority, especially in conservation areas and other architecturally sensitive locations.
