What’s important about the number 221? Granted, it’s the first bit of Sherlock Holmes’ address and the year in which Emperor Elagabalus adopted Alexander Severus as his heir (according to Wikpedia). Not only that, but 221 is the number of green VC deals that were done last year, according to DowJones’ VentureSource report worth $3 billion, up 47 percent on the year before.

Apparently, the US took the lion’s share of the investment at $2.52 bilion and 159 deals, worth 8 percent of all VC investment.

Europe got $360 million and 56 deals, up 27 percent year on year; China however dived spectacularly – in 2007, $129 million was invested, compared to $424 million the year before. Ouch. The report did note that a lot of IPOs went off, so it’s not all bad news.

Biggest winners were two electric carmakers, Project Better Place in the US and Think Global in Europe with $200 million and $67 million respectively.

“What’s really encouraging is that the cleantech industry is still in its infancy in the U.S.,” said Ms. Canning. “In fact, our data shows that 59% of all U.S. investment in the sector is going toward companies in the product development phase, which suggests that funding for clean technologies is likely to continue as these companies continue to develop and start generating revenues.”

In the U.S., the median deal size for a cleantech company stands at $8 million, up from $7.5 million in 2006. By comparison, the median deal size for all industries in the U.S. in 2007 was $7.6 million.

For European cleantech companies, the report showed that the median deal size rose from $2.3 million in 2006 to $3.3 million in 2007. The median round size for a cleantech deal in China in 2007 was $11.8 million, down from $15 million in 2006.

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