Yale endowment guru David Swensen is seeing a number of opportunities in “green” investments, writes TheEnergyCollective.com’s Marc Gunther.

“Yale University’s influential $16.3 billion endowment has taken stakes in startup companies aimed at developing clean technologies, Chinese solar and wind turbine manufacturers and in timberland certified as sustainable,” Gunther writes in analyzing the school’s latest annual report.

Gunther, who has previously interviewed Swensen multiple times, says Swensen has in the past been “skeptical about the whole notion of social or environmental investing,” which “makes his appetite for green investing even more noteworthy.”

Gunther says that Yale’s report shows its venture capital portfolio has more than $100 million (as of June 30, 2009) invested in more than 70 clean tech startup firms. “Two promising companies are highlighted: Silver Spring Networks, a Silicon Valley-based firm that enables development of the smart grid, and Mascoma, a cellulosic ethanol startup based in Lebanon, New Hampshire,” he says.

The endowment also owns shares of solar cell manufacturer Suntech Power Holdings, and HT Blade, which is China’s largest turbine blade manufacturer, Gunther adds. And the school has sizable investments in timber, which it considers an environmentally friendly fuel source and building material.