Optimum angle for solar panels

It's pretty obvious that you get more energy from a solar panel when it is pointing directly at the sun. If only the sun would stay still you could just point your array directly at the sun and life would be easy.

It doesn't stay still. Quite apart from the east-west daily variation, the sun is lower in the sky in winter, and higher in the sky in summer. So, if you're not going to go for an expensive motorised tracking system, what's the best angle for your solar panels?

It turns out it's not a simple question. It depends on whether you want the maximum amount of energy from your solar panels over the course of the year (which is probably the case if you have a grid-connected system for example), or whether you're more concerned about maximising the output in the middle of winter, when the output is at it's smallest (which is likely to be the case if you are operating remote scientific equipment for example).

For a particular place it also depends on the amount of cloudiness (when it's cloudy you may get slightly more power by keeping your panels horizontal), and whether there are any obstructions that block out the sun when it's low in the sky.

However, for what it's worth, here's a map of what the European Commision reckon is the optimum angle for solar panels to maximise annual yield. Personally, I wouldn't bother getting my protractor out however. Getting your panel out by 5 or 10 degrees will make a barely noticeable difference to the amount you generate.

You might also be interested in:

• Annual yields from solar arrays across the UK