While consumer Internet companies are getting crowded with newer and wealthier angel and seed funds, cleantech is seeing a drop both in overall investment dollars and early-stage investing. In fact, the overcrowding of angels backing Web startups — perhaps best evidenced by  the recent Angelgate debacle in which top investors were accused of “colluding” to discuss startup valuations — is a problem that cleantech wishes it had.

“For the last decade plus, we have been trying to get more people into our tent,” said Ira Ehrenpreis of Technology Partners at the Renewable Energy Finance Forum (REFF) West, a cleantech conference which took place late last week in San Francisco.

In the last year, the opportunities for cooperation between angels — wealthy individuals who invest their own money in startups — and venture capitalists — professional money managers who back growth ventures — have only increased, Ehrenpreis and others argued. As venture capitalists have pulled back from riskier early-stage investing, they have encouraged angels to fill the void.

“In our portfolio of 20-plus companies, we took classic early-stage risk in two deals. We need something tangible that we or our partners can evaluate. There is a role for super angels willing to take risk,” said venture capitalist Tim Woodward of Nth Power.

But angels, even so-called super angels who are especially active investors, should also beware. Green technology investing is much more capital-intensive than the information technology investing to which super angels are accustomed.

“The super angel model got created around Web companies that can be built around $5 million or $10 million of capital,” said Woodward. “If you can write a check for a million, you still own a lot of the business. If you can write a check for $1 million and [the business] needs $50 million, you may not own enough to make the transaction worthwhile. (Super angels are) absolutely needed, but I am not sure they will stay in this sector that long.”

Angels and their checkbooks are more than welcome in the green field, in other words — but there are reasons why angel-scale cleantech investments haven’t taken wing.

Yoni Cohen is a JD-MBA student at Yale Law School and the Wharton School at the University of Pennsylvania. Born in Israel, he is a former college basketball writer for Fox Sports. Follow him on Twitter at @cohen_yoni.

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