From As rooftop solar surges, states hit brakes

Hawaii generates most of its electricity by burning imported oil, giving it the dubious distinction of the country’s highest electricity prices. And over the past two years, as the price of solar panels plummeted, Hawaiians realized they had a budget-minded alternative to oil. As one, they began going solar.

Now, so many Hawaiians have installed rooftop panels that entire neighborhoods — and soon, entire islands — have maxed out the amount of rooftop solar power the energy company wants on the electrical grid. Barring expensive studies no one wants to fund, solar development in these areas grounded to a halt. Homeowners’ and developers’ rush to solar power has run smack into a grid unprepared for their demands.