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Post insightNet metering policies vary wildly by state — check before assuming solar ROI
Net metering (selling excess solar production back to the grid at retail rate) is what makes residential solar financially viable in most markets. But several states have reduced or eliminated net metering (California NEM 3.0 cut export rates by 75%). Before signing a 20-year solar loan, verify your utility current net metering rate AND whether it is grandfathered. A system designed for $0.30/kWh export that gets $0.05 changes the entire payback calculation.
Solar panel efficiency matters less than system design and shading analysis
The difference between a 20% and 22% efficient panel is about 10 watts per panel — maybe $200 over 25 years. But a single chimney shadow crossing one panel can reduce entire string output by 30-50% if microinverters or optimizers are not used. Per NABCEP guidelines, a proper shading analysis (Solmetric SunEye or similar) is worth more than premium panels. System design beats panel specs every time.