The solar power sector continued to pull in the most investment, with 84 deals worth $1.4 billion -- more than a quarter of the total $4.85 billion invested in clean technology in 2009, Greentech Media said in a year-end report. Last year's total was $7.6 billion.
Biofuel companies followed with $976 million in 44 rounds, while investment in water tallied more than $130 million.
The volume of deals -- 356 -- rose slightly from the previous year's total of 350 deals, the report said.
Among the sizable venture capital deals in 2009, the group noted the $198 million venture capital investment led by Argonaut Private Equity for solar thin film player Solyndra, which filed in December for an initial public offering.
The group also noted key acquisitions and initial public offerings in the clean technology sector, such as German conglomerate Siemens' purchase of solar thermal player Solel for $418 million and battery maker A123 Systems Inc's strong IPO debut. (Reporting by Laura Isensee; Editing by Gary Hill)