The best direction for a roof with solar panels is dead south. Except if you're in the Southern Hemisphere when you want it to be facing north. Which is why solar panels are like bath water spiralling down the plug hole.
But few people in Guildford have a roof that faces exactly south. And few people in Guinea have a roof that faces exactly north. So the key question for many of us is, "How much solar generation do I lose if my panels don’t face exactly south?"
Which is the best angle for solar panels?
The optimum roof angle of photovoltaic panels in the UK is 35-40 degrees. The exact angle depends on the latitude. Which is why the best roof angle will be different in other parts of the world.
For various reasons we have recently been looking at the performance of solar panels in Africa, Mexico and Spain.
If like me, you are curious as to the performance of solar and the best orientation for solar panels in other parts of the world, here’s what we found.