Solarun - Frequently Asked Questions
Solarun - FAQs
Solarun assistant

Clicking on a category on the right will take you straight to questions on that subject within the list below. Otherwise you can simply scroll down through the list. If you can’t find the answer you need, click here to email us your query – one of our experts will get back to you as soon as possible. Our figures were updated in August 2012, but you may need to see Government sources for the very latest Tariff arrangements.

About solar power

Q: How does a solar electric system work?

A: The panels we install on your roof contain photovoltaic cells. As sunlight falls on the cells, they convert the suns energy to DC electricity. A small box called an inverter, normally installed in the loft, converts the DC electricity to AC electricity, which is fed to the existing consumer unit in your home – from where it contributes to the electricity used in the home.

Q: What happens when the sun isn’t shining?

A: The photovoltaic cells will generate electricity as long as daylight is falling on them, so they will still be producing electricity on a cloudy day.

Q: Can I still use electricity from the national grid?

A: Yes, whenever you need to. The existing electrical circuits in your home are not changed, but as you are generating your own electricity you will need to buy less from an energy supplier.

Q: What happens at night?

A: When it is dark the solar panels will not be generating electricity, and you will buy any electricity you need from your energy supplier in the conventional way.

Q: Is solar power viable for every property?

A: We would always advise that you take advantage of our free site survey before you make a decision. The panels will work anywhere, but are at their most efficient on an unshaded, south facing roof. So if your home is overshadowed by large trees or buildings it could be problematic. Also of course, the roof needs to be accessible for the installation, and strong enough to support the panels – but we will check all that out for you.

Q: Will I have an independent power supply during power cuts?

A: Unfortunately not. During a general power cut the system is automatically shut down. This has to be done to ensure the safety of people who may be working to restore the fault, as your system could still be feeding electricity back into the grid.

Q: Will I have to turn the solar energy system off when I am not at home?

A: Absolutely not. When the house is unoccupied (for example, when you are at work or away on holiday) the system will continue to produce electricity, and because you are not using it, it will be fed back to the national grid. You will receive payment for the electricity you supply – this is called the Export Tariff.

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Investing in solar power

Q: The UK isn’t known for its long hot summers, so is solar energy really practical in this country?

A: Yes it certainly is. The photovoltaic cells in the panels on your roof don’t rely on sunshine to make them work. As long as daylight falls on them they will generate electricity, so they will be effective almost anywhere in the UK – even on cloudy days.

Q: How much will I need to spend on a solar electric system?

A: It will vary from property to property. Take a look at the easy-to-use calculator on this site. It will give you an indication of the energy output of various systems, and how much they are likely to cost. Installing more panels enables you to generate more electricity and increases the potential savings. But obviously the size and shape of your property will affect the number of panels you can install. We would be pleased to provide a free site survey and give you specific advice and costings.

Q: Will it take many years for me to recoup my investment?

A: You may be surprised to see how dramatic the financial returns can be. The Energy Savings Trust suggest that typical installation costs can be recovered within fifteen years. But it does depend on where you live in the UK. The calculator on this site will give an indication of the payback periods for various levels on investment.

Q: Will future technology changes reduce the cost of systems– would I do better to wait to invest?

A: The Government’s Feed-in Tariff scheme has been designed to give you the highest benefit now, and it is very unlikely that any technology breakthrough could be introduced quickly enough to change that position. Take a look at any of the independent money advice websites and you will see that they are very supportive of investing as soon as possible!

Q: How can I work out what the savings will be?

A: You can use the calculator on this site. Tell us whereabouts you are in the UK, and
how much you are likely to invest in a system. The calculator will show your likely savings in electricity, and the income you could receive through the Feed-in tariff. Our figures are based on those provided by the independent Energy Savings Trust – so you can check what you are likely to save on their website as well.

Q: How can I find out what size of system I will need?

The calculator on this site will give you a good indication, and then our free site survey will confirm your best approach. Most properties need a system between 2 and 3 KWp which the Energy Saving Trust suggest is likely to be able to generate about 75% of the electricity needed to run your home.

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Q: Will I need planning permission?

A: Solar roof systems are ‘permitted developments’, so it is unlikely that you will need planning permission. But if you live in a listed building or in an ‘Area of Outstanding Natural Beauty’ you are advised to check with your local planning authorities.

Q: How long does installation take? Is it disruptive?

A: Most systems are installed within a day. It isn’t necessary to change the existing wiring of your property as it only involves installing some small units alongside your consumer unit, and running cabling up to the panels on the roof.

Q: Could I install a DIY solar system myself?

A: In order to claim the Feed-in tariff the system must be installed by a company certificated under the Microgeneration Certification Scheme (MCS). Only those installers are authorised to display the MCS Approved logo you will find on our site.

Q: Can I have panels fitted to an outbuilding or garage?

A: That may be possible, but we would need to conduct a site-specific survey for you. The survey is completely free and there is no obligation on you whatsoever. Please get in touch for advice.

Q: How are the panels fixed onto the roof?

A: We install roof hooks, which fit above the roof tiles and support the panels. The roof is not changed, damaged or compromised in any way.

Q: Are heavy cables needed to carry the electricity down from the panels?

A: No. Only the conventional domestic cabling that you will be familiar with is involved. We don’t have to alter any of the mains cabling that comes into your home from the street.

Q: How can I tell if my roof will support the extra weight?

A: Our site survey will ascertain if the roof construction is suitable. We are very experienced in all aspects of roof work and will be able to advise you if any additional support is necessary – but it is very unlikely to be necessary.

Q: Who designs the system and the layout of panels on the roof?

A: There are a range of standard designs, which accommodate most house styles, and we will be able to advise you on the one, which will be most suitable for your property.

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The Feed-in tariff

Q: If I have a relatively small installation and use all the electricity I generate myself, will I still receive any payment?

A: Yes you will, because there are two parts to the Feed-in Tariff scheme that the Government introduced in April 2010 and reviewed during 2012. The first is a ‘reward’ for installing a micro-generation system and it pays you on a tariff rate even if you use all the power yourself. Typically you will currently receive about £370 a year, but it depends on the size of system that you install. The second element of the scheme is the ‘Export Tariff’, under which you receive a separate payment for any electricity you export to the national grid.

Q: How will I receive the Tariff payments?

A: It’s a Government backed scheme, which is operated through the energy suppliers. They will normally make Feed-in payments on a quarterly basis, but your chosen supplier will be able to give you all the details. They are also responsible for metering any power you export to the grid, and for paying you for that.

Q: Where does the money for the Tariff payments come from?

A: The Government has introduced a small levy on every UK energy consumer. The money raised is used to encourage people to install micro-generation systems.

Q: How long will the Feed-in tariff scheme last?

A: For the solar electric systems that we install, the scheme is now guaranteed to run for at least 20 years. The tariff payments are index linked so they will retain their value over that time. This means that once you have recovered your set-up costs (usually in about fifteen years) you will continue to receive payments, and so be generating a tax-free income as well as saving on electricity supply bills.

Q: Could a future Government change the 20 year guarantee to payments?

A: The Feed-in Tariff was introduced through Primary Legislation and it would be a breach of the Government’s contract if it didn’t run for 20 years. Payments cannot be changed over this time other than in line with inflation.

Q: When is the best time to install a system?

A: There is no time like the present! The tariff payments are calculated using the rates in place when your system is installed. The Government may decide to change the amount that new applicants are able to claim, and it is possible that it may be reduced. Installing now will guarantee you receive the current rates.

Q: Does the Governments incentive scheme require me to carry out other energy-efficiency work?

A: The maximum Feed-in Tariff is only paid for properties that have an Energy Performance Certificate of D or above. A lower Tariff rate is paid for properties rated below D.

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Q: How long will the solar panels last?

A: The panels come with a manufacturers guarantee of 25 years and the expectation is that they will have a working life of at least 40 years.

Q: What sort of maintenance costs should I expect?

A: Solar energy systems are virtually maintenance free. The only likely maintenance is if they were to become obscured by dead leaves or bird droppings for example. In that case, they would only need a simple clean – which we would be pleased to undertake for you.

Q: How is the glass of the cells kept clean?

A: The panels are designed with a self-cleaning surface, so that any dirt is washed off by usual rainfall, providing that they are correctly installed. Even in extreme conditions it is estimated that dust will only reduce the efficiency of the panels by about 10%.

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Other questions

Q: What happens if I move house?

A: The benefit of lower electricity bills and the regular income from the Feed-in tariff will be transferred to the new owner. This is likely to add value to your property and secure you an advantage in the market place over similar properties without solar systems installed. As more and more people become aware of the savings that are achieved, it will increasingly become an important selling feature.

Q: Your calculator uses units called kWp to show the power of the system – what are these?

A: A kilowatt hour is the unit of measurement that is shown on your bill when you buy electricity from a supplier. It is the amount of power consumed when you use 1000 watts for 1 hour. For example, a 100 watts light bulb left on for 10 hours would use 1 kWh.

Q: How many square metres of solar panels are required for a domestic system?

A: This depends on a range of factors, such as where you live and which direction your roof faces, but roughly speaking 8 square metres of panel will produce approximately 850kWhs of electricity per year. The Energy Savings Trust estimates the needs of a typical home to be 3,300 kWh per year, so that’s about one quarter of the total power you are likely to use.

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