The League of Conservation Voters has awarded John McCain a 0% rating in its 2008 environmental scorecard. His score is so low because he hasn't bothered to show up for a vote for months, but as Think Progress notes:
McCain’s environmental record isn’t so poor just because he’s been absent. His lifetime LCV rating is 24 percent, with his highest rating at only 56 percent in 2003-2004. McCain has voted against tax incentives for renewable energy, updating building code standards for energy efficiency, and modernization of the electricity grid. Furthermore, he does not support any increases in fuel efficiency above existing law.