The source is BP's Statistical Review of World Energy. You can read an interesting if cynical critique of this report by Jeremy Leggett in the Financial Times, arguing that the statistics are a cover up and that an 'energy crunch' is upon us.
Relatedly, BP do publish some data about Jeremy's area, solar PV. Solar PV grew nearly 50% in 2009, which is surely good news. But total capacity is still only enough to meet about one twentieth of 1% of global demand for electricity. So Jeremy's article just offers a reminder of how little protection we really have against the energy-crunch scenario.
