Chimney Shading and Solar

How does chimney shading affect solar panels?

Chimney shading is the most common rooftop shading issue for UK solar installations. KEY FACTS: (1) Shadow moves throughout the day as the sun crosses the sky. (2) Shadow is longest in winter (low sun angle) and shortest in summer. (3) IMPACT WITH STRING INVERTER: one shaded panel can reduce the whole string by 20-50%. (4) IMPACT WITH MICRO-INVERTERS/OPTIMISERS: only the shaded panel is affected (5-15% loss on that panel). (5) A good installer uses shading analysis software to predict shadow paths and position panels accordingly. SOLUTIONS: avoid placing panels in the primary shadow path. Use micro-inverters (£800-£1,200 extra) or SolarEdge optimisers (£500-£1,000 extra). In some cases, removing the chimney pot (if unused) reduces the shadow.