Commercial Solar PV Installation?
Contact us for a detailed information pack on installing solar pv on a commercial building. 0845 643 2528 / 01829 261 765..

What are Photovoltaic (PV) Panels?
Photovoltaic panels convert sunlight directly into electricity that can be used to run appliances and lights. Photovoltaic cells generate energy even when it is overcast and cloudy as they absorb scattered light.

How are PV panels fitted?
Photovoltaic panels can be mounted on a roof or ground mounted. Ideally the roof will be south facing, or near to at an angle of 30 degrees with the horizontal for optimum performance. The panels produce DC electricity, so a small inverter will be fitted inside the house, to change the DC into AC (used in all normal homes and the Grid). Installation is clean, with minimal disruption and no extra space needed indoors.

How many are needed?
Any number of PV panels can be connected based on available space, to provide as much electricity output as required. A basic 2kWp solar panel installation will generate around 1500 kWh per year.

Which roof should they go on?

The optimum orientation for solar photovoltaic panels is due south at a 30 degree latitude tilt in the UK. Systems facing East of West will lose efficiency but are still viable.  Systems such as solar trackers maximise exposure to the sun by following its path.  This will increase efficiency by 20% during the winter and up to 50% during summer over static systems.

Will it supply all my electricity?
The average household consumption is 3300 kWh per year. The 2kWp system would supply nearly 50% of annual consumption. A 4 kWp system could provide all electricity needs depending on consumption for the average household. Recent advice by the Energy Savings Trust (August 2011) has shown that some houses are only able to use 25% of what they generate, this depends on usage of appliances and occupancy during the day. 

What size system do I need?
This depends on your budget, available roof space (unless ground mounted) and energy output required.

What is a Grid Connected System?
Photovoltaic panels can be connected to the Grid through the local electricity supplier. Surplus electricity can be sold back to the supplier.
 
What are Stand Alone Systems?
In remote areas with no grid-connection, electricity produced can be stored in a battery bank.

What Are Grid Support Systems?
This mixes battery and the Grid, with any excess solar electricity produced after the battery is fully charged, is then sold back to the Grid.

What Maintenance and installation is required?
As there are no moving parts in the PV panels, there is no noise or need for maintenance other than an occasional clean as required. Solar panels come with a warranty of over 20 years. During installation of roof systems, scaffolding is required. Installations usually take three days.

How much do they cost?
Installation costs are under £4,000 per kW installed including VAT. The price will vary depending on the size of individual installations. Please fill in the enquiries form for a quote.

Is Planning Permission Required?
Most domestic properties in England and Scotland do not require planning permission before installation of photovoltaic solar panels. Those in Conservation Areas, listed buildings and Areas of Outstanding Natural Beauty or World Heritage Areas must consult local Planning Departents.  Wales are reviewing planning permission requirements, some areas do not require permission, contact your local planning department. Non residential buildings still require planning consent.

How does a photovoltaic cell actually work?
Solar PV systems consist of modular panels made of silicon, which react directly to sunlight by generating electric current. An inverter changes the DC (direct current) generated by the panels into AC (alternating current).

How long does the installation process take?
For an average domestic system, the installation process rarely takes more than two days, with minimal disruption. Scaffolding is required for work on the roof.  For larger commercial PV installations, we can work within required deadlines as necessary.

What is the Installation Process - what do I need to do?
For a domestic system we supply, install and test all of the equipment, we arrange the scaffolding, notify your district network operator and will provide you with all the warranties and certifiactions you require to receive the feed-in tariff. All you will need to do is contact your electricity supplier and ask for a microgeneration pack and then relax whilst we do the rest. Once installed, you will have all the information to fill in your pack and send back to your supplier to receive your feed-in tariff.

Can I really sell back to the National Grid?
Yes. The Feed-in Tariff pays a premium on every unit of electricity generated by pv panels with an additional bonus for every unit of electricity exported back to the National Grid. This is paid for everythign you generate regardless of whether you use it in the property. This Tariff is administered by Ofgem. Electricity suppliers are responsible for paying the reward to customers.

What is the Feed-in Tariff?
The tariff began in April 2010. For every unit a solar panel system generates up to 4kWp, the Government will pay 43.3p.  For systems up to 10kWp the tariff is 37.8p and up to 50kW the tariff is 32.9p. Once you install, your feed-in tariff is secure for 25 years and will increase with RPI/inflation. The Feed-in tariff is due to drop on April 2012 for new installations.

Is TAX Payable on any income?
HMRC announced in December 2009 that tax will not be payable on income from the feed-in tariff for domestic PV installations. Commercial installations will pay tax at the applicable rate.

Do PV Panels Work In The UK?
Generally temperatures above room temperature reduce the efficiency of pv solar panels, making the UK a good climate for photovoltaic technology.  The panels require ambient light rather than direct sunlight to generate electricity so they work even on overcast days.

Solar PV Panels For Schools?
The Green Electrician works with schools and companies who supply schools with solar pv. For more information on Solar PV in schools .

 

Choosing your Solar PV Installer and avoiding the Rogue Traders
We suggest asking the following questions to ensure that you are getting a good deal, a good price and a good service:

- Always ask to see a copy of the MCS certification and check whose name is on the certificate and they will be installing your system.
- Ensure, where possible, that you can deal directly with the company that will be installing your panels and you are not being passed to an anonymous third party.
- Check who is accountable for the work, including insurance and warranty for electrical and installation work, along with panel product and performance warranty and inverter warranty.
- Confirm that the solar panels and inverter on the quote are MCS accredited and are a recognised label with customer services that can handle warranty issues. 
- If you are offered a cheap price, there is usually a reason for this - is the company new, inexperienced, using cheap products?
- Do they employ roofers, will they leave the roof as they find it?
- Is the company an REA member and adheres to the REAL Consumer Code of Conduct, protecting the rights of the customer - this covers the integrity of the information provided, through to keeping your deposit safe and ensuring your are never misled or mis-sold solar pv.

Which Solar Panel To Chose - Not Every Panel is Equal

The Green Electrician only uses top manufacturers for all our products, including panels, inverters and meters. This gives our customers confidence in the quality of the product and also the warranties behind the products.

Glass
Thickness – thinner glass leads to less rigidity of the panel. When panels are being carried, this can result in movement along the panel, causing hairline fractures in the silicon.
Pressure - Quality glass is made at high pressure, which means it can sustain far more stresses and strains e.g. the weight of a person standing on the glass. Poor quality glass can lead to vibrations, stresses and strains during high winds.
Anti Reflective - Is the glass anti reflective and manufactured by a top quality glass manufacturer such as Pilkington, Saint Gobain, Krystal.  For example, quality module manufacturers are generating an extra 5 Watts per panel due to the extra clarity of the glass, whereas budget manufacturers are likely to lose output due to lower glass clarity.

Junction Box
Lower quality - junction boxes can result in a higher failure rate of a panel. This is due to poorer quality components within the junction box. Full gel sealed junction boxes are becoming the norm in quality manufacturers, whereas budget products will not be fully sealed and could allow moisture through. There is a heat/ fire risk with poor quality junction boxes as was seen a few years ago when faulty junction boxes led to a catastrophic failure of panels, resulting in fires.

Diodes - The diodes in a junction box can have a failure rate if there is a lot of fluctuation in sunshine and shade. Diodes can heat up and this will result in failure. If a diode fails, the panel will not perform as well. This will then affect all the panels in a string since a string will perform as well as the lowest performing panel.  The heat produced in faulty junction boxes can result in a fire within the junction box

Connectors - If connectors are not original connectors i.e. they are "compatibles", there could be a problem with water penetration, rust, etc

Frame Quality

If the aluminium frame is not manufactured to the highest standard, there could be a failure in the material, resulting in metal fatigue. Panels could then possibly fall off the mounting frame. If panels are glued or crimped, are they glued/ crimped properly? Will they stand the test of time?

Stringing of Silicon Cells

If cells are not stringed together properly, there could be a breakage in the connections, resulting in a panel performing poorly. Soldering can be an issue if this is EVA Sheet

EVA sheet is a heat melt adhesive film. EVA sheet is used for encapsulating PV modules.

The EVA is like a plastic sheet which goes between the silicon cells and the glass. This encapsulates the silicon to the glass. Poor quality EVA can result in clouding of the EVA sheet over a period of time. If this happens, sunlight cannot get through, resulting in panels failing completely.

Rubber Seal
Solar panel failure is often caused by water damage to the panel, sealant, or connections. If the sealant is of poor quality, this can allow moisture to get through.Warranty
How good is the warranty of the manufacturer? Will they be around in 10 years time, let alone 25 years? How strong is their Balance Sheet?

Small manufacturers generally refuse to deal with "problems", claiming there is nothing wrong with the product. Larger companies sort it out immediately.　

 For further information: Contact us for a copy of our details Solar PV Residential or Commercial Information Packs 0845 643 2528 / 01829 261 765