Will a solar panel produce electricity on a cloudy day?
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 so-called 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.

Will solar panels work in the winter?
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.

Will a solar panel supply electricity 24 hours a day?
No, solar panels convert light into electricity. So as the light reduces in the day so does the output of the solar panel.

What size solar panel do I need?
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 (see FAQ How to calculate your solar panel needs), 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. Obviously the 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.

What is a charge controller?
This device controls the charge to the battery. When the battery is fully charged the controller disconnects the solar panel from the battery.

Do I need a charge controller?
We recommend that charge controllers are used with 15watt solar panels and above.

What is an inverter?
An inverter takes the DC (direct current) from the solar panel and creates a useable form of AC (Alternating current). Inverters are power hungry, so it is best to purchase (if possible) a product that operates on 12vdc.

Can equipment be used directly from solar panels?
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.

Is maintenance required on solar panels?
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.

What are the possible problems?
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.

What problems might there be with mounting a solar panel?
Try not to fix panels horizontally as rain will collect in the frame and not cleaning the panels will reduce the output. Make sure there is an air gap beneath the panel.