If you wonder why America’s utilities are rattled by the explosive growth in rooftop solar – – and are pushing back — William Walker has a story for you. A flip-flop wearing Walker stands in his driveway pointing to a ubiquitous neighborhood feature – solar panels on the roofs of five of six houses nearby. He lives in Ewa Beach, a development on the sultry leeward coast of the Hawaiian island of Oahu built on land cleared of sugar cane fields. Shade is scarce and residents here call their homes “hot boxes,” requiring almost round-the-clock air conditioning. Hawaii , which imports pricey oil to power its electricity grid, has the highest utility rates in the nation — at 37 cents a kilowatt-hour, they’re more than double California and triple the national average. With bills for 1,600 square foot houses like these running as high as $400 a month, solar […]