San Francisco Chronicle: President Obama’s vision of a clean energy future of wind farms and solar plants comes with a catch: It will require thousands of miles of new high-voltage power lines to move the energy from where it’s most abundant, in the California desert or the plains of the Midwest, to power-hungry urban centers. Obama’s allies in Congress, including House Speaker Nancy Pelosi, D-San Francisco, and Senate Majority Leader Harry Reid, D-Nev., are pushing legislation that would give federal …