Global investment in sustainable energy amounted to $148 billion in 2007, a 60 percent gain over 2006, according to a United Nations report (PDF) Tuesday.
That will grow to $600 billion past 2020, reported New Energy Finance, a consultant to the U.N. Environment Programme.
The report forecast that an anticipated U.S. carbon tax, along with a new administration in Washington, D.C., and shifting attitudes by banks, will drive clean tech growth in America beyond the borders of California, despite the credit crisis.
Public investment in wind topped $11 billion globally last year, but none of that came from the United States, the report said. Wind power developer Iberenova, for instance, made the largest initial public offering in Spain in December 2007.
In 2007, solar companies raised more than $9 billion, which the U.N. attributed largely to Chinese companies aiming for the U.S. market.
And financing for energy efficiency technologies surged by 78 percent, amounting to a relatively modest $1.8 billion.
Among other highlights of the research:
Early venture capital investment expanded 112 percent to $2 billion in the same time period, while mergers and acquisitions rose 52 percent to $25.7 billion. Private financing of ethanol companies drove growth early in 2007, but plunged near the middle of year as feedstock prices spiked.
Biomass and waste to energy technologies expanded by a whopping 432 percent.
Sustainable energy added 31 gigawatts to worldwide capacity, growing by 23 percent.
Research and development in the sector totaled nearly $17 billion in 2007, of which $10 billion came from corporations and $7 billion came from government sources.
Developing nations are a widening target of new investment, which grew 22 percent to $26 billion from 2004 to 2007.