Todd Woody writes:
While electricity prices are expected to continue to rise in the years ahead, the installed cost of a photovoltaic system continues to drop.
The plummeting price for photovoltaic electricity means that installations are spreading beyond states like California that feature both high electricity prices and generous subsidies for solar.
I suspect that generous subsidies are the primary motivation. Even at $3500 per KW and 300 sunny days a year, the payback period is more than 10 years when compared to the average commercial cost of 14 cents/KWH. The cost of PV systems would have to halve again to make them commercially viable without subsidies.
Read more at The US corporate boom in solar power explained in five charts – Quartz.