Ten years ago, when Ron Pernick predicted that solar power would be a $23.5 billion industry by the decade's end, skeptics scoffed. After all, worldwide sales of photovoltaic solar equipment in 2000 were just $2.5 billion. Pernick's prediction had to be wrong. It was. The global solar market last year hit $71.2 billion. Pernick is co-founder and managing director of the Clean Edge Inc. market research firm, and for the last 10 years, his outfit has produced annual tallies of alternative energy sales around the world. The latest report, released today, shows a decade of remarkable growth. The market for solar power, wind power and biofuels still pales when compared with that for fossil fuels (Exxon Mobil, for example, made $383.2 billion last year). But clean-energy technology is no longer stuck in a niche. It went from relative obscurity 10 years ago to being one of the dominant market forces today," said Pernick. Wind power has grown from a $4 billion global market in 2000 to $60.5 billion in 2010. Ten years ago, alternative energy firms received less than 1 percent of the venture capital invested in the United States. Last year, they got 23 percent, with investments totaling $5.1 billion. For biofuels, the report's data only stretch back to 2005. But in that time, the worldwide market for ethanol, biodiesel and other biofuels has grown from $15.7 billion to $56.4 billion.