Refining Poop Power: Wastewater in, Cellulosic Ethanol Out

Qteros: from feedstock to fuel. (Qteros photo)

There's no nice way of saying this: A group of green-minded entrepreneurs are making a clean-burning car fuel out of, well, poop. They don't call it that, of course -- they prefer to call it "municipal wastewater" or "sewage sludge," but trust me, that's what it is.

I come from a family of engineers, and my father was a pioneer in reclaiming potable water from sewage. I have a photo of him, in a hard hat, quaffing a glass of the stuff. So this is exciting news for me. In a two-step process, Israel-based Applied CleanTech (ACT) start by removing cellulose (the part of the plant we can't digest) from both the sludge and agricultural liquid waste, then Marlborough, Massachusetts-based Qteros ferments this treated material into cellulosic ethanol using a fast-acting microbe sourced from Massachusetts' Quabbin Reservoir.

Qteros' fast-acting q-microbe. (Qteros photo)

It's called Sewage Recycling System (SRS), and ACT spent six years developing it. CEO Israel Biran says that its technology can solve the headache of sewage sludge disposal, and Qteros co-founder Jeff Hausthor says its customers can be "every municipality that has a wastewater treatment plant." And unless your town is dumping its sewage right into a bay or lake, it has one of those plants.

Bill Frey, CEO of Qteros, said his company's mission is to find the most effective way to make low-cost, non-food ethanol. Cellulosic ethanol processes have not yet been commercialized--a hurdle to getting this collaboration off the ground--but Frey said in an interview that Qteros will be looking for partners next year to make that happen.

According to ACT President Dr. Refael Aharon, a fairly large wastewater plant, handling a population of two million people and processing 150 million gallons a day, would have enough capacity to keep a small ethanol plant supplied with processed cellulose feedstock. And for every ton of that treated feedstock (which they call "Recyllose") some 120 to 135 gallons of ethanol can be made.

It's hard to see the downside of this. But wait, there's more! Last week, I was in Los Angeles with Daryl Hannah, Ed Begley, Jr. and author David Blume discussing the wonders of alcohol/ethanol fuel. Blume, author of Alcohol Can be a Gas, champions whole systems that make use of salvaged "waste" products. Here he is, on video, talking about the possibilities of ethanol fuel:

Blume has, in fact, worked on natural marshes that filter municipal wastewater and sewage. Blume's book reports that 35 acres of cattail marsh, by absorbing nutrients and chemicals, could treat five million gallons of secondary sewage each day. Arcata, California was a pioneer of that kind of natural filtration.

Cattail is the most effective sewage-filtering plant, Blume says, and it grows prolifically in marshes, yielding up to 150,000 pounds of biomass per acre. A great byproduct, of course, could be ethanol made from all that plant material -- up to 10,000 gallons per acre.

Here's Blume's amazing conclusion: Growing cattails on just 6,367 acres in each county in the U.S. (accounting for 1.46 percent of agricultural land) we could produce 200 million gallons annually, and treat all of our country's sewage. Why aren't we doing this across America? Is it just because we get squeamish when we talk about poop?