"In March 2011, a massive 9.0 earthquake off the coast of Japan precipitated a cascading series of events that ultimately sparked Hawaii’s rooftop solar boom more than 4,000 miles away.
As Japan shuttered its nuclear fleet and ramped up production from its oil-fired generators, global demand for oil increased, and so did prices. Since petroleum fueled 80 percent of Hawaii’s electricity generation in 2011, when oil prices rose, so did the state’s retail electricity rates—up to more than three times the US national average.
Hawaii residents felt the pain through their utility bills. To alleviate the financial burden of electricity, customers increasingly installed cost-competitive solar systems, often financed through third parties for $0 upfront, with excess generation compensated at retail rates through utility net metering programs. Solar adoption exploded at an unprecedented speed and magnitude, rapidly vaulting Hawaii into the echelon of leading states for installed solar capacity per capita."