After two failed attempts to extend renewable-energy tax credits set to expire at the end of this year, the U.S. House of Representatives is preparing to introduce yet another bill next week that could save the crucial credits.

In the meantime, hundreds of business leaders – including representatives from Google, Kleiner Perkins Caufield & Byers and TechNet – have signed a letter urging Congress to extend the credits (see Earth2Tech post).

But despite the uncertainty about the credits, which the companies say would lead to a loss of jobs and the forced cancellation of 42 gigawatts of planned renewable-energy projects in the United States, venture capitalists apparently still are counting on returns from greentech investments.

Funding announcements have flooded the news this week in advance of President's Day, especially insolar As Greentech Media reported earlier this week, Infinia Corp. snagged $50 million for concentrating solar, Odersun raised $58 million for thin-film solar and Moser Baer injected $1.5 billion into its thin-film solar subsidiary (see Funding Roundup: Lights, Solar, Money and Moser Baer to Pump $1.5 Billion into Thin Film).

Here are some of the most interesting deals in just the last few days since our previous roundup:

PRIVATE:

  • Solar-concentrating developer Cool Earth Solar got a $21 million lift Thursday for technology that uses inflated mirror concentrators to turn sun rays into electricity (See Concentrating Solar Gets a Cool $21M). The Livermore, Calif.-based company didn't disclose who paid for the round. However, Cool Earth did say additional closings could happen in the next 60 days.
  • Europe-based Low Carbon Accelerator lit up the energy-efficient lighting company Lumenergi with a $1.6 million investment Wednesday. The investment gives Low Carbon a 14-percent equity stake in Lumenergi, which is developing technology that dims fluorescent lights when their full brightness isn't needed. The investment is the first part of a funding round expected to total $7.5 million, but the total amount is dependent on Lumenergi reaching some undisclosed milestones.
  • Self-described "stealth" startup Adura Systems grabbed an undisclosed round of financing to develop near-zero-emission serial-hybrid technology for buses and trucks (see press release). "Serial-hybrid vehicles use internal-combustion engines to send electricity to an electric motor, which then moves the wheels. This differs from a parallel hybrid (think of the Toyota Prius) which is driven by both the combustion engine and the motor directly. Wind-farm developer New Frontier Renewable Energy made the investment.
  • On Valentine's Day, Canada-based StormFisher Biogas hooked up with a new honey. The renewable-energy company, which is developing biogas installations across North America, announced it had formed a partnership with Boston-based private-equity firm Denham Capital Management. Together, the two have promised to develop a C$350 million ($347 million) fund to fill a portfolio full of biogas projects. For more about the newly minted couple and their fund, check out this post on Clean Break.

PUBLIC:

  • China's Shenzhen Topraysolar Co. on Wednesday said it would offer up to 40 million shares, for 10.79 yuan per share, to raise up to 432 million yuan (about $60 million) on the Shenzhen Stock Exchange. The company hopes to be the first "pure-play" Chinese solar-cell manufacturer to debut on the exchange, as other Chinese solar companies -- such as Suntech Power (NYSE: STP), LDK Solar (NYSE: LDK) and Yingli Green Energy Holding Co. (NYSE: YGE) -- have selected U.S. exchanges instead (see Reuters story).
  • Octillion Corp., an alternative-energy technology incubator based in Auburn Hills, Mich., said Wednesday it had raised $3.7 million in a private placement of shares and warrants. The company apparently is pursuing building-integrated solar technology. In its announcement, Octillion said it is developing a transparent window capable of generating electricity and plans to consider acquiring other related photovoltaic technologies. The bulletin-board-traded firm, which trades under the ticker "OCTL," said it could raise up to $4.6 million more if all the warrants are exercised.
  • WorldWater & Solar Technologies said Wednesday it had raised $35.6 million from The Quercus Trust through a private placement of 20,000 shares of preferred stock (see the announcement). The preferred shares equate to 20 million shares of common stock. As part of the deal, Quercus also can purchase up to 29 million more shares for $52.6 million. The company said it will use the money to finish constructing a 50-megawatt solar-production plant in Texas, as well as to hire staff, expand globally and bolster its research and development. Quercus -- which already owned 11.5 percent of WorldWater before the deal -- now owns about 24.1 percent.