California electricity rates are high enough to justify the cost(.32-.36 per KW) . I did most everything myself and put a 7.625 kW system on the roof two years ago. It will be paid off in about another year and a half so I figure I’ll get 10 or 12 years of free power. Last year my tru-up was $68(total power used minus power generated)this year the tru-up was 34. It really depends on the weather though because if there are clouds, you don’t make any power.