America’s biggest solar power developers are stockpiling panels to lock in a 30% federal tax credit set to start phasing out next year, a strategy that could backfire if projects do not materialize or panel prices slide substantially.  Duke Energy, 8minute Solar Energy and Shell-backed Silicon Ranch are among those working to claim the full subsidy, which is available to firms that either start construction or spend 5% of a project’s capital cost by the end of 2019. Consumers who purchase residential solar this year are eligible for the full tax credit, but the rules that allow the subsidy to be locked in now for systems installed much later apply only to companies. North Carolina-based Duke, for example, plans to claim the maximum […]