What Affects Solar Output?

What affects how much solar panels produce?

8 factors affect UK solar output (ranked by impact): (1) Roof direction: south=100%, east/west=80-85%, north=55-60% (15-45% impact). (2) Shading: partial shade reduces 10-30% (10-30% impact). (3) Location: south England vs Scotland = ±15% (10-15% impact). (4) Tilt angle: optimal 35°, flat roof = 87% (2-15% impact). (5) Soiling: dirt/droppings reduce 2-5% (2-5% impact). (6) Inverter efficiency: 96-98% conversion (2-4% impact). (7) Temperature: panels lose 0.4%/°C above 25°C (1-3% impact in UK). (8) Degradation: 0.3-0.5% per year (cumulative). Direction and shading are the big two — everything else is minor.