NOCT solar panel rating standards are much more realistic - actual wattage output is around 25% less than the normal rating!

Solar Panel tilt angle affects the output. About 45% is good - adjusting by season is better.

Solar panel direction has an effect on output

Due South (in the Northern hemisphere) is optimum. South-East and South-West are OK, but never North!

Auto-tracking (following the sun across the sky) increases energy output

Clean those panels!

Regular cleaning can increase electricity generation by 10% to 25%

Since 1986