China does everything big, and cow poop-to-power projects are no exception. 250,000-head dairy operation in northeast China plans to open the world's largest cow manure-fed power project in September, according to General Electric Co., the company supplying four biogas turbines to the Liaoning Huishan Cow Farm in Shenyang. For comparison, the largest U.S. dairy farms have 15,000 cattle.

The project deals with a few environmental problems in one swoop. As the dairy industry grows in China, it is generating more smelly and polluting waste. Booming electricity demand brings bigger challenges in transmitting power to rural areas, where many dairy farms already happen to be located.

Not to mention climate change. According to a recent U.N. report, the farm-to-table carbon footprint of the dairy sector accounts for 4 percent of greenhouse gas emissions globally. About half of the emissions from milk are methane.

"There is a huge potential in this," said Michael Wagner, marketing leader with GE Energy. "We are looking around the world to expand." But biogas is nothing new. In China, household digesters have been in use for decades. And by 2005, there were already 1,500 large-scale biogas plants at livestock farms and industrial waste sites.

China's newest livestock digester will reduce piles of dung, yield fertilizer and heat, and will supply 38,000 megawatt-hours of power annually to the state's power grid, enough to meet the average demand of some 15,000 Chinese residents. It produces biogas, a methane and carbon dioxide mix emanating from manure, grease, sewage or other organic materials allowed to stew in an oxygen-free chamber.

The government has big plans to use biogas to meet some energy goals. China wants 300 million rural residents to use biogas electricity by 2020, in part from 10,000 large-scale biogas projects on livestock farms, according to a 2007 plan from the National

Development and Reform Commission. As with many other clean technologies, when China decides to encourage a sector, often, it succeeds. Wagner said the Huishan farm invested roughly $1.5 million in total capital for the biggest project. The China project, he said, makes "economic sense."

Elsewhere economic payoff may come later

Around the world, that is not always the case. The barriers to the expansion of biogas are about economics, not technology, and how long it takes for biogas projects to pay off varies country by country. In European countries with the best incentives, projects pay for themselves in four to five years, Wagner said.

But in the United States, the livestock digester business is dicier, according to several in the business.  Karl Crave developed his first digester project at Crave Brothers Dairy Farm, a 1,700-acre farm his father and uncle started in Waterloo, Wis. Now, as project manager of Clear Horizons LLC, he is planning several projects in a state with some 14,000 more dairy farms to choose from.

"In Wisconsin, it's a great opportunity to take advantage of our natural resources, which ends up being manure," he said. Still, he said, of those thousands of cattle operations, only 24 have digesters now.

Some farmers are intrigued by digesters primarily to manage odor and manure issues, he said. They might view it as a side benefit to also generate power or heat for the farm. But for him to raise the funds needed to start a large project that sells power to the grid, like the Crave Brothers' operation does, better incentives are necessary.

"Economically, these projects need to make sense in order to build them," he said, noting that projects in the United States can take seven to 10 years to pay off. "Obviously, that's not great."

Chu sees U.S. lagging behind China in renewable incentives Others are taking a different approach. The developer Microgy Inc. runs what it says is probably the world's largest renewable natural gas plant in Huckabay, Texas. The company collects dairy cow manure and other agricultural organic wastes from nearby farms, purifies the biogas, and injects it into a commercial gas pipeline, where it is sent to California to be burned by Pacific Gas & Electric.

Michael Hvisdos, Microgy's executive vice president, said that there are several factors that boost the project. The co-digestion of other organic wastes increases gas production by several times. The gas it produces yields 8 to 10 megawatts, more electricity on average than the China facility. Gas prices can also provide some help, and so can the fact that a utility already has the power facility. Huckabay does not need GE's biogas turbines.

"We're sustainable without incentives," he said. But both he and Crave said better incentives, such as high renewable electricity rates, were needed if biogas projects were to gain ground here. As Microgy struggles to raise capital for new projects, what would also help would be a tax credit on par with what the solar, wind and ethanol industries already receive, Hvisdos said. Crave added that carbon offsets have yet to be a major driver behind projects.

The biogas field could be one more example of the ways the United States is falling behind China. Yesterday, Energy Secretary Steven Chu said that the United States is lagging behind China, which provides strong tax incentives for a host of renewable energy technologies. "We're not doing so well," Chu told an audience attending a clean jobs conference in Washington yesterday. "Time is running out."

It might not help for the Obama administration to sell the "green jobs" connection in this case, however. Crave often gets people telling him, "That's a shit job." He says it's true.

Hong Nhung