Washington, D.C.--If it's dirty, it's gold.

That's one of the underlying themes at Creating Climate Wealth, a two-day conference taking place in Washington, D.C. this week. Instead of talking aboutsolaror wind, a large number of the discussions and talks revolve around cleaning up ports, recycling and other somewhat anonymous industries not generally associated with fresh breezes and blue skies.

The term "gritty green" was uttered by Craig Cogut, the founder of Pegasus Capital Advisors, a private equity firm with a number of investments in efficiency. He used the term to refer to iGPS, a portfolio company that specializes in shipping pallets fashioned from recyclable plastic.

There are roughly 90 million shipping pallets in the U.S. and millions more worldwide, he noted. Until recently, virtually all of them were made of wood. The plastic pallets weigh 45 pounds, versus 75 pounds for a wood pallet, he noted, which in turn reduces fuel consumed in transportation. You also don't have to chop down forests to produce them.

Within three years, iGPS has managed to carve out a 15 percent market share, landing deals with such companies as General Mills, Kraft and Pepsi.

"We live in a resource-constrained world," he said. "We grew up in an era of plenty. That era is over."

Meanwhile, David Steiner, CEO of Waste Management (WM), provided a number of examples of how his company has begun to shift from garnering revenue from trash hauling to recycling services. Wal-Mart, for instance, contracted with WM to help it reduce the solid waste from its stores by 95 percent. Five years ago, Steiner said, that would have been viewed as a threat to the company's core business: WM, after all, manages 290 landfills.

Nonetheless, the company helped Wal-Mart come up with a recycling strategy. The solid waste stream from California Wal-Mart stores dropped from 1,200 containers to 60. Revenue from Wal-Mart's California operations, however, rose 28 percent and profitability went up 25 percent.

WM also worked with a famous doll maker to make its product more recyclable.

"If you told me when I went to Waste Management that I would give plastic surgery to Barbie, I wouldn't have believed you," he said.

In all, WM recycles 8.5 million tons of stuff a year and wants to triple that figure over the next decade.

Some other fun solid waste facts: WM has 20,000 trucks on the road each day, consumes 200 million gallons of diesel annually, and spends $500 million on trucks a year.

"Any company that develops hybrids or lightweight materials (for trucks) will get part of that pot of gold," he said.

WM also has a joint venture with Valero that will attempt to develop a liquid fuel from the carbon dioxide that bubbles off of its landfills, and the company has invested in Harvest Power, which has created an anaerobic digester that turns organic waste into methane.

Americans generate 4.5 pounds of waste a day, he added.

Despite all of the positive proof points, green as an industry still faces an uphill battle. Most large private equity firms have still not made large investments in sustainability because it still sounds too much like philanthropy, said Cogut. Foreign firms are actually more active in this respect, he added.

Cogut believes that the connection between jobs and sustainability has to be emphasized more clearly. Another Pegasus company, LED light maker Lighting Sciences, has only a handful of employees in Florida now, he said, but will soon expand to nearly 1,000. More examples like this can underscore the connection.

Meanwhile, the clock is ticking.

"My impression is that we may implode because of resource scarcity. We need to decouple economic growth from carbon emissions," said Jose Maria Figueres, the former president of Costa Rica and the CEO of the World Economic Forum. "There is no Planet B."