Photovoltaic Panels on Your Roof?

What are PV Panels?

Solar photovoltaic (called solar PV) panels convert energy from the sun into electricity.

Solar panels are made of a thin layer of semi-conducting material sandwiched between a sheet of glass and a resin. When exposed to daylight, the semi-conducting material becomes ‘energised’ and produces electricity. There are four basic types of PV panel: monocrystalline, polycrystalline (or multicrystalline), hybrid and thin film (or amorphous silicon). Hybrid are the most efficient. All are made from silicon but differ in the way the material is cut and treated.

Can PV Panels by fitted in Marshfield?

Fitting solar panels to a roof in Marshfield is not straightforward: the village is in an Area of Outstanding Natural Beauty (AONB) and is a Conservation village and so nothing is easy.  Planning permission may be required – so enquire of the South Glos planning department.

How do I buy the best?

Buying solar panels is a significant investment that may take years to pay-back (about 5-7yrs for early installations).

“Which” (the Consumer Association) investigated how well firms assess properties during the initial sales visit. In 2011, they posed as a potential customer and invited 12 firms to a house rigged with secret cameras to see whether they were complying with the consumer code they signed up to.  They recently found that solar panel mis-selling continues. In March 2017, five men were charged with conspiracy to commit fraud when selling solar panels.

Some of the things they found out:

  • Breaching the code by offering a discount valid for 24 hours only and offering a ‘first come, first served’ discount in exchange for providing regular meter readings (‘monitoring’).
  • Failing to mention ongoing costs, despite prompting,
  • Not going inside the loft to check suitability for installation of solar PV.
  • Sending a salesperson, not a surveyor, but still giving a quote, estimate or price.
  • Not taking into account the fact that part of the roof was in shade
  • Not asking questions about energy usage or lifestyle.
  • Underestimating the time it would take for the system to pay for itself.
  • Failing to mention that the inverter (which is an essential part of a PV system and turns the current generated into usable AC current) would need replacing and so contribute to maintenance requirements and ongoing costs.

There are many solar panel installers so collect a range of quotes for comparison. Search for a certified installer on the Microgeneration Certification (MCS) website ( If you plan to apply for the Feed-in Tariff (a financial incentive paid to those with solar PV), then you need to use a MCS-accredited installation company that installs MCS-certified products. Also check that your installer is a member of the Renewable Energy Consumer Code (RECC) (

Is it worth it? What return will I get?

Possibly the most important consideration is that it is renewable energy and will reduce the demand for ‘normal’ electricity and so help tackle climate change.

However, a typical south facing house in Marshfield with 16 panels installed in 2011 has produced about 3400 units per annum.  Using payments from a Feed In Tariff (which was set high for early installations) has meant that after 7 years the panels are now providing a pay-off that means both electricity and gas usage cost nothing.  BUT the returns are now likely to be very different!

Currently FIT payments are 4p per unit plus a fixed amount – visit the ofgem website:

Installation costs are reckoned to be about £1250 per kilowatt, but some have managed £1000 per kilowatt.

See also

Most people believe it is still worth it –but you must act fast because of the deadline.

What is a Feed in Tariff?

You can apply to get payments from your energy supplier if you generate your own electricity, eg with solar panels or a wind turbine. This is called a ‘feed-in tariff’ (FIT):

HOWEVER, PLEASE NOTE that new applications for the Feed in Tariff is planned to stop in about three months (about March 2019)

Current information can be found at:

Some other useful/interesting web-sites