What the stimulus package means

I was reading this article in the NY Times about how the stimulus package breaks down.
"Programs to promote energy efficiency and renewable energy sources are big winners in the stimulus package, receiving more than $45 billion in new spending and tax breaks."

Maybe we use the site to explain exactly how renewable energy is funded (now and in the past)? We'd have some good sources at NREL. I just don't think I've ever read anything that coherently explains how the government is/isn't supporting renewable energy.

-Tiffany