Frequently Asked Questions

What is Solar PV

Photo Voltaics - the first part of the word being 'photo' which means 'light' and the second being 'volt' which is a unit to measure electrical voltage. 'Photo Voltaics' literally means 'electricity from light' - converting light into electricity.

How Do Solar PV Panels Work?

Solar panels consist of PV cells encased in a metal frame covered in a thin layer of glass, which are attached to your roof. Each cell is made from one or two layers of semi-conducting material, usually silicone. When light shines on the cell it creates an electric field across the layers, the stronger the light, the more electricity is produced .

The strength of a PV cell is measured in kilowatt peak (kWp). This is the amount of energy the cell generates in full sunlight.  

Daylight hits the photovoltaic cell and is converted into clean sustainable electricity. The inverter converts the electricity from direct current (DC) to alternating current (AC), for use in the home. When the solar energy system is producing more power than is needed, it is exported (sold back) to the grid. At night, power is imported from the grid in the normal way.

Will they work in winter?  

Yes, solar panels work all year round. The important thing to bear in mind is that solar power depends on the intensity of the light, not just direct sunlight. So even when it's overcast and raining, your solar panels will be producing clean electricity to help power your home. Even in winter, in the shorter days, they will be generating electricity.

Are they Suitable For My Property?

Solar Panels work best on buildings with roofs that face South, South East or South West. Your property must be free from anything that overshadows the roof i.e. building or trees. If the roof is in shadow for part of the day, the effectiveness of the system can decrease, however, this does not mean solar panels cannot be fitted, Our surveyor will advise you when he assesses your property.

Do I Need Planning Permission?

In most cases, planning permission is not needed, however, if you live in a conservation area or listed building, we would always recommend checking with your local planning authority first.

How Much Roof Space Will I Need?

The more roof space, the better. However, we design the systems to suit your roof and budget.

How Much Electricity Will It Generate?

There are five main factors that will impact on how much energy your solar PV system will generate:

  1. The total size of the PV array (measured in Kw)

  2. The latitude of the location.

  3. Which direction the PV panels face.

  4. What slope (angle of your roof) the panels are mounted on.

  5. Anything which shades the panels.

Will It Provide All My Electricity?

This depends on what your household power consumption is. The easiest way to calculate this figure, is to have a look at your previous bills. For example, The Energy Saving Trust calculates that the average three bedroom house uses 3300KWh a year (assuming cooking etc are on a non electricity supply).

What if I produce more energy than I need?  

Whenever your panels are producing more electricity than your home is using, it will flow back into the grid for other homes to use. The great news is, you will be getting paid for this. This means you can be sure your energy bills will be even less and none of your clean, green electricity will be wasted.

Is solar power expensive and what are the benefits?  

Installations to existing properties start from 2,995.

After the initial outlay, there are several financial advantages to installing a solar PV system:

  1. A tax free income for 20 years index linked to inflation 
  2. Helps 'future proof' your home against rising fuel prices
  3. Makes your property doubly attractive to price conscious house buyers
  4. As fuel prices continue to rise, energy efficient renewably powered homes will continue to sell at a premium

How long will it take to install?  

The average domestic system will take 2 days to install.

Will there be a mess?  

No. Our installers will lay dust sheets in the house and thoroughly clean up after they have finished.

Is the workmanship and the installation guaranteed?  

We are accredited solar PV installers and members of the REAL Assurance Scheme. We offer a 10 year workmanship guarantee from the date of installation. The inverters carry a standard 5 year warranty which can be extended to 25 years (ask the surveyor for details). All our panels carry a 5 year warranty and a 20 year + efficiency warranty.

Will it still generate electricity for my use if there is a power cut?  

No. The inverter needs a mains supply to operate. This is a safety feature which stops your system from feeding back into the grid when there may be someone working on a fault on the grid.

How much maintenance is required?  

Systems require very little maintenance other than ensuring that shading from trees etc doesn't become a problem. Solar photovoltaic systems are silent in operation, have no moving parts and are virtually maintenance free.



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