Find out the answers to some commonly asked questions about installing and running solar PV microgeneration systems.
Why should I use solar PV?
We need to reduce our dependency on fossil fuels and get our electricity from renewable sources, such as solar power.
What are the benefits of solar PV?
- Reduce your bills and protect against electricity price rises
- Earn an income with the Government's Feed-In Tariff
- Reduce your carbon footprint
- Maintenance-free, silent running and a long lifespan of around 35 years on average
What is the difference between solar hot water and solar PV?
Solar hot water (or solar thermal) systems use the heat of the sun to warm water. The systems use a panel (or collector) on the roof to convert the heat of the sun into energy for warming water. Solar PV systems convert the energy from sunlight directly into electricity that can be used throughout your home or sold back to the National Grid.
How do solar panels work?
A solar photovoltaic (PV) panel on your roof converts sunlight into electricity. When sunlight hits a material called a semiconductor, which is the main part of the panel, the semiconductor releases electrons which causes a flow of electricity. This flow of electricity is converted by an inverter into "usable" electricity.
What are the effects of shade or cloud on a solar PV?
The amount of electricity generated by a solar PV system depends on the intensity of the sunlight. This will be reduced if it is cloudy or the panel is shaded by trees or other buildings. The panel will still generate electricity though, but not as much.
What do I need for a solar PV system?
A typical system is made up of:
- Solar PV panel array
- Mounting brackets
- Inverter to convert DC electricity into AC
- Generation Meter
- Switchgear and Wiring
Does solar PV need batteries?
No. The solar PV system is connected to the National Grid so batteries are not necessary.
What types of solar panels are available?
Energy Station can provide virtually any type of panel. The panels we install are generally higher performance than the panels available from high-street retailers and generate more electricity.
How much electricity will solar panels generate?
This depends on a number of factors, including the type and number of panels used, the orientation of the panels and whether there is any shading. The Energy Saving Trust estimate that an average 3-bedroom home uses 3kWH of electricity per year, so to provide all the electricity needed you would need a 3-4 kW system. As you are still connected to the National Grid, you can still use electricity from your normal supplier should you need to.
Is solar PV connected to the National Grid?
Yes. Any surplus electricity you generate can be sold back to your electricity supplier. If you need extra electricity then you use and pay for it in the normal way.
Can I get paid for the electricity I generate?
Yes. All energy providers are obliged to purchase the energy generated by homes and businesses. A new Government incentive, the feed-in tariff, guarantees a minimum income from solar PV systems for 25 years.
What is the feed-in tariff?
In April 2010, the Government introduced an incentive scheme to encourage homeowners and businesses to install solar PV systems. This guarantees payment for electricity generated but the guaranteed amount decreases over time to encourage people to install systems sooner rather than later. You can read more about the feed-in tariff.
How do I get money back?
This depends on your energy company. Some may send a cheque periodically or some may deduct it from your regular bill.
How much will a solar PV system cost?
This depends on the type and quantity of panels you are installing. It also depends on your building and the costs of installing - this is generally only known after a survey of the building. A typical system will costs around £9999 and is regarded as a good investment since fuel prices are expected to rise over the next few years.
Can I get a grant for solar PV?
No. Grants were previously available but these have now been superseded by the more lucrative feed-in tariff.
Is planning permission required for solar PV?
Generally, domestic properties do not require planning unless your home is listed or in a conservation or other protected area. You will need to contact the planning department of your local authority for clarification.
How long does it take to install solar PV?
It takes around 1 to 2 days to install but this depends on the building and the nature of the installation/
How much space is required for solar PV?
We recommend a space of 8 square metres per kWp.
How long will a solar PV system last and is there a guarantee?
Most manufacturers offer a warranty of 25 years and systems can last up to 40 years, although the performance of the panel will reduce with time. It is estimated that the system will still perform at 80% of its efficiency 20 years after installation. Inverters are guaranteed for 5 years.
What maintenance and cleaning does a solar PV system need?
Very little. The inverter may need replacing every 5 years.
What happens if there is a power cut?
If there is a power cut, the solar PV system is shut down automatically as a safety precaution. Once power is installed, the PV system will have instructions on how to restart it.
What if I need to expand the solar PV system?
Additional panels can be added easily, although some components may need to be upgraded.
Will a solar PV system work in the UK, and will it work during the winter?
Yes, but due to seasonal variation in the length of the day, output will vary.
How much carbon dioxide will a solar PV system save?
A typical 2 kWp system will save almost 1000 kg of CO2 per year based on official Government estimates.
If my house is not south facing can I have split panels, one on the front and one on the back?
Yes, but there may be extra cost incurred and you may need a larger system than you would otherwise.