I researched historical rates in San Diego (upcoming solar install prework) and prices have increased an average of 5%/year for 10 years running. This felt like

I researched historical rates in San Diego (upcoming solar install prework) and prices have increased an average of 5%/year for 10 years running. This felt like a reasonable assumption to me, although to be cautious I used 3%. Rates will change! Energy doesn’t look like it will get cheaper, especially with EV fleet rollouts. Accounting for planned 2 EV purchases at 10k miles/year, the largest system I can build on my roof has something like $150k savings against <$50k cost over 20 years. That gives a lot of room for unexpected issues and feels like a wise bet to take.