Solar installer GroSolar has raised $10 million in its second round of venture-capital funding, CEO Jeffery Wolfe said Wednesday at ThinkEquity Partners' ThinkGreen Conference in San Francisco.

NGP Energy Technology Partners led the round.

White River Junction, Vt.-based GroSolar last year raised $2.25 million in its first round from SJF Ventures, Calvert Social Investment Fund and Allco Financial Group. Wolfe said previous investors also participated in the latest round.

While he didn't say how GroSolar will spend the money, Wolfe said the company plans to expand its residential services geographically next year. He also said the company is working on some new technology unrelated to solar panels or inverters, which convert the direct current yielded by solar-power systems into the alternating current used by most household appliances.

While Wolfe didn't give more details, those exclusions make it sound like GroSolar is developing technology to make panels easier or cheaper to install. But he added that other aspects, such as driving down sales and project management costs per watt, also are important.

"If you only focus on the technology and the installation [to] drive costs down, you lose, because you can only make people run around their roof so fast," he said. "You can only take out so many pieces of installation."

GroSolar's round is one of a windfall of fundings in greentech so far this week. Here's a roundup of some of the others:

Beyond Landfills: PlascoEnergy Grabs $35M

To the Ottawa-based PlascoEnergy, a pile of garbage is a treasure trove.

Out of solid waste, the startup says it can make clean energy, potable water, salt, construction products and fertilizer. It is testing its first commercial plant in Ottawa and it has three more large-scale projects in the works in different parts of the globe.

Now, investors with deep pockets are paying close attention. On Tuesday, the company announced it had raised $35 million from the energy-oriented private-equity firm First Reserve. Existing investors added $14 million, and Pasco said First Reserve will add an additional $115 million next year.

PlascoEnergy's system uses plasma technology to create and refine gases out of waste materials. A metric ton of waste that goes into the system comes out as two kilograms of waste, according to CEO Rod Bryden.

The synthetic gases created in the process are used to generate power, producing 1.4 megawatts of power out of 1 metric ton of waste, which Plasco then sells. The company also earns revenue in garbage-tipping fees from municipalities and private companies.

The concept of converting waste to energy is nothing new, as companies and municipalities have been burning garbage and tapping into landfills to create energy for decades. The U.S. Energy Information Administration estimates that there already are 400 projects in the United States that capture methane in landfills and convert that to energy, and 90 plants that burn trash to capture energy.

But Bryden said PlascoEnergy's system is cleaner and more efficient that those solutions, which produce greenhouse-gas emissions and are less efficient than some other energy-generation technologies.

"There's no combustion at any point in our conversion system, and no emissions, and that is dramatically different than anything you will find in the waste business," Bryden said.

That pitch has been enough to attract upcoming projects in Alberta, Ontario, and Barcelona. The company also has proposed a project to the city of Los Angeles.

Pesticides "Inspired by Nature": Agraquest Raises $20M

Out to prove that green pesticides aren't an oxymoron, the Davis, Calif.-based Agraquest announced Monday that it had raised $20 million in new venture-capital funding for its biopesticides.

Founded in 1995, the company has created pesticides out of naturally occurring microorganisms, which it metes out through agricultural distribution companies.

Chief Financial Officer Derek Fairchild-Coppoletti said Monday that the company has seen a surge of interest in the natural pesticide space in recent years as consumers and companies have become more aware and concerned about the environmental impacts associated with agriculture.

"People in many markets are interested in what we would call 'cleaner' food,'" said Fairchild-Coppoletti. "Our products are naturally inspired using plant extracts and microbes. Nature has done the bulk of work and we are enhancing the work that nature has already done."

Four out of the company's five products are certified organic and the products have been found to leave little to zero trace on the food.

Despite that, according to Cairchild-Coppoletti, many of the company's customers are nonorganic farmers who are attracted to Agraquet's pest controls because they allow workers to enter the field soon after the crops are sprayed. Other pesticides require days to weeks before workers are allowed to enter the field, Fairchild-Coppoletti said.

Agraquest has raised a total of $100 million, and executives have openly discussed their desires to move to an IPO.

"We see this as very large market," Fairchild-Coppoletti said.

Cash for Biofuels: OPX Gets $3.6M From VCs, Other Projects Get Government Support

OPX Biotechnologies, based in Boulder, Colo., on Wednesday said it raised $3.6 million in its first round of venture-capital funding (see Earth2Tech and VentureBeat posts). Mohr Davidow Ventures led the round, and X/Seed Capital, which previously gave the company seed funding, also participated. The company is engineering new microbes to make biofuels and biochemicals.

Other biofuels researchers also received cash this week. The U.S. Department of Energy said Tuesday it plans to invest up to $7.7 million in four biofuel projects by Emery Energy Company, Iowa State University, the Research Triangle Institute and the Southern Research Institute. The latest investments bring the DOE's total funding for biofuels research and development to more than $1 billion so far this year.

VCs Back Bicycle-Inspired Wind Tech and Solar Cells

Viryd Technologies raised $2.1 million for a bicycle-inspired wind-power technology (see VentureBeat post). The company, which is moving to San Antonio, Texas, is a spinoff of Fallbrook Technologies, which makes transmission technologies for bikes.

In other news, Cyrium Technologies, based in Ottawa, on Monday said it had raised $5.5 million for its gallium-arsenide-based solar cells (see Clean Break post). The company claims the cells, intended for concentrating solar-power systems, can convert 45 percent of the sunlight that hits the cells into electricity. Investors included Chrysalix Energy Venture Capital, Pangaea Ventures and BDC Venture Capital. The company claims its cells, intended for concentrating solar-power systems, can convert 45 percent of the sunlight that hits the cells into electricity.