What percentage of the world's population does not have electricity?

"Some 1.6 billion people, about one quarter of the world?s population,
have no access to electricity today. Eighty percent of these people
live in rural areas of the developing world, mainly in South Asia and
sub-Saharan Africa where rapid urban migration and population growth
will occur over the next
several decades."

Source: IEA, "The Developing World and the Electricity Challenge,"
Jan. 2005, http://www.iea.org/Textbase/work/2005/poverty/blurb.pdf.

Of course, this is only an estimate. An undated Greenpeace document
puts the figure for people without access to electricity at "more than
2 billion."

Source: Greenpeace, "Solar Generation: electricity for over 1 billion
people and 2 million jobs by 2020,"
http://www.greenpeace.org/~climate/climatecountdown/solargeneration/solargenback.pdf.