I missed this when it first came out, but Matthew Wald and Kate Galbraith had a very sharp piece in The New York Times about how utilities around the country are struggling to meet state laws that require them to get a certain portion of their power from renewable sources by such-and-such a date. California's big utilities, for instance, are likely to miss their targets entirely. The main obstacles: Congress keeps bobbing and weaving on tax incentives for solar and wind (the production tax credit was only renewed this year at the 11th hour, and probably would've expired entirely had Wall Street not demanded a bailout package); utilities have had trouble obtaining financing for and overcoming local opposition to new projects; and, oh yes, transmission lines in this country are woefully inadequate, rarely extending to the plum wind and solar spots.
There's a decent chance taht Congress will quickly pass a national renewable portfolio standard next year—requiring, say, utilities to get 15-25 percent of their energy from renewable sources by 2020 (a version of this bill sailed through the House and just fell short in the Senate last year). But it looks like the only way these targets will be reachable is for the federal government to take the lead—and spend a bunch of money upfront—expanding and strengthening the national grid. So it's nice to see that Harry Reid, among others, is talking seriously about making "green transmission" a central component of any economic stimulus package.