If McCain cares about Energy, why was he the ONLY Senator not present to cast his vote?

Did you know that you can save fuel and run your car on water

David S questioned:

Sen. John McCain missed two essential energy votes on H.R. 6, The Energy independence and Wellbeing Act, in December 2007. These votes – on December 7th and 13th – would have bunged argument and allowed a vote on an energy bill that included essential tax incentives for renewable energy sources – a bill to strengthen national wellbeing, lower energy expenditure, reduce global warming, grow our state and start new jobs, and boost American energy Independence. These votes were essential to making a $21 billion investment in sterile, renewable energy and energy efficiency, including a $3,000 tax credit to help effective families meet the expense of fuel-efficient plug-in hybrid and gripping vehicles. On the daylight of December 13th, Sen. John McCain was the only United States Senator to not vote on this rate.

http://www.autobloggreen.com/2008/06/24/is-john-mccains-300m-battery-prize-a-excellent-thought-pelosi-chimes/

Did you know that you can save fuel and run your car on water