green.bmpOk, you’ve heard versions this headline before: “Investments in clean technologies doubled last year, compared to the year before.”

So far, definitions of clean technology have remained vague, and we’ve remained suspicious about the accuracy of industry data on investments in this area.

Today, Dow Jones Venture One has released a more precise definition of what “clean technology.” Earlier, the group also tightened the definition of “Web 2.0” investments, which greatly improved upon previous efforts.

In 2006, venture investors pumped $1.28 billion into clean technology companies in China, Europe, Israel and the U.S., the group said today. That’s about double the $664.1 million invested in 2005, according to the research, which was compiled the data with help from Ernst & Young.

And here’s their definition:

Because of the significant level of attention being focused on cleantech, VentureOne’s research department adopted a strict methodology for categorizing potential companies in this new industry. They were defined as companies that directly enable the efficient use of natural resources and reduce the ecological impact of production. Areas of focus include energy, water, agriculture, transportation, and manufacturing where the technology creates less waste or toxicity. The impact of cleantech can be either to provide superior performance at lower costs or to limit the amount of resources needed while maintaining comparable productivity levels.

The most active global investors in cleantech in 2006 include Draper Fisher Jurvetson, DFJ Element, Khosla Ventures, Nth Power and Rockport Capital Partners.

See more info in the table below:

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