A plan to build a 100-mile undersea cable linking power grids on Hawaii’s islands would help meet the state’s ambitious renewable-energy goals, reduce its heavy dependence on imported oil, and cut electric bills for consumers.

It could also become an important test case for the ability of existing grids to rely on power from renewable sources. If it proves, as its backers hope, that grids can take more power from renewable sources than the maximum levels currently assumed by the industry, that would be a big boost to plans for offshore wind farms along the U.S. East Coast. Keep reading →