The survey by market researcher Dow Jones VentureOne and consulting firm Ernst & Young found that venture capitalists in the United States, China, Europe and Israel boosted investments by 93.5 percent over the US$664.1 million spent in 2005.
More than two-thirds, or US$883.6 million, of all "clean technology" investments in 2006 were made by US investors, VentureOne data showed.
China bumped out Europe as the second largest market, with 12 deals attracting US$221.8 million, up from US$85.5 million in 2005. Europe attracted only US$157 million in 2006, but three times as many deals, reflecting smaller average deal sizes.
"Global climate change, high oil prices, accelerated growth in emerging markets, energy security and the finite nature of resources are some of the key drivers," Gil Forer, director of Ernst & Young's venture capital practice, said in a statement.
The largest clean tech investments in 2006 were US$75 million in solar panel maker NanoSolar of Palo Alto, California and US$50 million in ethanol and biodiesel producer Altra Inc. of Los Angeles, VentureOne analyst Josh Grove said in an interview.
The third largest venture financing was US$40 million invested in solar cell maker Trina Solar Ltd. ahead of its initial public offering late in 2006.
The category, called "clean technology" by its supporters, includes renewable energy and also water, agriculture, transportation, and manufacturing where the technology creates less waste or toxicity.
Read full story: Clean Tech Venture