Michael Ahearn, who stepped down as the First Solar CEO in 2009, has re-emerged.

Ahearn is behind True North Venture Partners, which will invest in early-stage energy, waste, water and food startups. While energy has garnered billions from VCs, those other sectors have lagged somewhat. The picture, however, has begun to change, and recycling is shaping up to be a growth market. The world, meanwhile, is expected to endure rising food prices and chronic droughts in the future.

The firm will put $100,000 to $25 million into companies.

Ahearn was a co-founder of First Solar and served as CEO for years. The company's history stretches back almost 20 years. In the late '90s, however, First Solar had a breakthrough in coming up with a way to produce cadmium telluride solar cells. It began to manufacture them in 2002. The rest is history. It now makes the cheapest solar modules (under 75 cents a watt) and jousts with Suntech for the number-one spot in the industry. (Savor the irony: neither Suntech or First Solar, two of the biggest IPOs in greentech history, received money from Sand Hill Road VCs.)

When Ahearn announced he was stepping down in 2009, he said he planned to work on behalf of the solar industry by lobbying and raising the profile of solar in Washington and state capitols.

"The manufacturing incentives will be useful sweeteners, but that won't substitute for creating a robust market," Ahearn said then. "You ought to get the policy and program right, and you can't leave it all to the states. Otherwise it'd be fragmented and underfunded."

Solar, arguably, needs more lobbying help than money. Either way, it's good to see him back.

Side note: rumors swirl that Nicholas Parker of the Cleantech Group is trying to raise a fund.