Answer :

- Renewable (Not finite)
- Doesn't contribute to global warming (Doesn't release CO2 and other pollutants like fossil fuels do)
AL2006

-- It's cheap (almost free), and easy to find (available almost everywhere,
about 50% of every year).

-- It's 'renewable'.  (There's no way for you or everybody on Earth at the
same time to use enough to make any dent in the available supply.  It'll
never run out.)

-- It's totally pollution-free.