New Enzyme Could Cut Cost of Ethanol Made From Waste

Source: DIANE CARDWELL • New York Times  • Posted: Wednesday, February 22, 2012

It is one of the holy grails of clean energy production: finding a way to make ethanol from the cellulose in biowaste like corn husks and household trash. Although several pilot projects are up and running — with many more in the pipeline — commercial production has remained elusive, with the costs remaining much higher than for producing ethanol from corn, or gasoline.

But in what may come as welcome news to oil companies that are paying penalties for failing to use cellulosic ethanol — a biofuel that, commercially speaking, does not yet exist — a big producer of industrial enzymes has developed an enzyme that can help wring more ethanol out of cellulose at a lower cost.

The company, Novozymes, already makes enzymes used to make numerous products, including household detergents, soft drinks and stonewashed denim. It plans to announce the new enzyme, Cellic CTec3, on Wednesday in advance of the National Ethanol Conference in Orlando, Fla.

To make cellulosic fuel, biomass — wheat straw, wood chips, cornstalks, household waste or nonfood crops like switchgrass — are broken down into a pulp, then mixed with enzymes to produce sugar. That is then fermented with yeast to become a liquid fuel that burns cleaner than petroleum-based gasoline.

“This is about bringing down the cost,” said Peder Holk Nielsen, executive vice president at Novozymes. “With corn and sugar-cane ethanol, you have a very expensive raw material and a simple process,” he said. The making of cellulosic ethanol, on the other hand, uses a very inexpensive raw material that is expensive to transform into fuel.

The company, which is locked in an enzymatic arms race with DuPont’s Genencor unit, says the new enzyme is more potent than its predecessor and competing products. Cellulosic ethanol makers have in the past needed large quantities of enzymes to make the fuel, so a significant cut in the amount needed would drive down costs. Mr. Nielsen said the new product could help bring the cost of cellulosic ethanol down to $2 to $2.50 a gallon, in line with gasoline and corn ethanol. “It makes it manageable,” he said.

Novozymes said it had a deal in place to supply the new enzyme to the M&G Group, which is to open a plant in Crescentino, Italy, this year with a capacity of 12 million gallons a year. It also has a deal with Fiberight, which plans to open a small plant in Lawrenceville, Va., this year and a six million-gallon plant in Blairstown, Iowa, next year. M&G plans to use wheat straw, nonfood crops and other feedstocks, while Fiberight plans to use municipal solid waste.