Frequently Asked Questions
Yes, a solar panel does produce electricity even when it is not placed in bright sunlight. On a normal cloudy day there is always enough diffuse light, by which the panel will produce electricity. However, the production of electricity is not as high as when the panels are placed in bright sunlight.
Yes, solar panels work on light not heat. The amount of sun hours will be less in the winter, as the sun rises later and sets earlier.
No, solar panels convert light into electricity. So as the light reduces in the day so does the output of the solar panel.
This depends on the load you have connected to the battery. You will need to calculate the watt-hour or amp-hours you are using in a period of time, and then having a rough idea of the amount of direct sunlight your solar panel will receive each day. The solar panel needs to supply approximately 20% more than your needs to compensate for variables, such as cloudy days etc. Winter will have shorter sunlight hours per day than the summer, but you can work on an average of approximately 4 hours sunshine a day in the UK over a year.
Yes, solar panels will run equipment direct, these could be loads such as fans & pumps, but make sure the load of the equipment is not equal to the output of the solar panel, as overcast or cloudy days will reduce the output. Solar panels with not run TV’s or radio’s (without battery backup), as they require a more stable voltage.
Clean using a non-abrasive cleaner. In the long term check the sealing especially in marine use and reseal with a silicon sealant if damage is suspected. Check battery connections periodically when you check battery levels. Fuse holders and connections should be kept dry and clean.
Failure of a solar panel is normally due to water damage to the panel itself or the connections. Also damage to the sealant around the frame could cause failure. Mounting the panel incorrectly, if it is fixed horizontally it may be able to collect water. Not a sufficient air gap beneath the panel can also cause damage.
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.
The optimum orientation for solar photovoltaic panels is due south at a 30 degree latitude tilt in the UK. Systems facing East or 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.
Photovoltaic panels can be connected to the Grid through the local electricity supplier. Surplus electricity can be sold back to the supplier.
In remote areas with no grid-connection, electricity produced can be stored in a battery bank.
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.
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 Departments. Wales are reviewing planning permission requirements, some areas do not require permission, contact your local planning department. Non residential buildings still require planning consent.
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.