Developers and installers caution Wisconsin must be sure the economy is ready for another run on renewable energy before the state rushes into building new anaerobic digesters.
â€œThereâ€™s not a lack of interest or motivation,â€ said Dennis Hatfield, a senior consultant with Madison-based environmental consultant RMT Inc. â€œBut there are a lot of economic uncertainties and a problem with the physical availability of funds.â€
But the construction industry is hungry for new opportunities, and builders should be excited about any state support for the digester projects, said Terry McGowan, business manager for the International Union of Operating Engineers Local 139.
â€œItâ€™s not as complex as a power plant, but even though the price tags are a lot lower, thereâ€™s going to be excavation and concrete work and pipe work, too,â€ he said. â€œThe man hours are there. If we can create jobs, we should get after it.
â€œTheyâ€™re a lot less expensive (than power plants). What can you lose?â€
Gov. Jim Doyle last week announced he wants to spend $6.6 million in state money to help build two digesters — large mechanical structures that convert cow manure to biogas — in Waunakee and Middleton.
The Waunakee project is estimated at $18 million, and Peter Taglia, staff scientist for Madison-based Clean Wisconsin Inc., said the project would be the stateâ€™s first communal digester, serving several farms instead of just one.
With 18 digesters operating around the state, Wisconsin leads the country in quantity, but Michael Tiry, president of Chippewa Falls-based Tiry Engineering Inc., said the rush of excitement that led to construction and installation a few years ago came with some problems.
â€œThere are problems, ranging from generating enough heat to keep them warm and avoid thermal shock, to issues with gas leaks and engines holding up under hydrogen sulfide corrosion,â€ he said.
The problems are manageable, Tiry said, and the technology is available to build better digesters. But he said the state still must determine how to better manage costs and collaboration between farmers and energy utilities.
The cost of upgrading utility service to rural areas is preventing the construction of more digesters, said Steve Dvorak, president of Chilton-based digester designer GHD Inc.
â€œItâ€™s whether the cash flow is there,â€ he said. â€œSome of these farmers have light utility lines, and to get these things up and moving, the power to a utility takes a heavier line, and the farmer might have to absorb that cost.â€
Eric Callisto, chairman of the Public Service Commission of Wisconsin, said the PSC should have a report ready for review next month analyzing buyback for digesters and other renewable energy. Rates of buyback are utility payments for producers who want to feed their power source into the grid.
â€œWisconsin is one of the national leaders when it comes to buyback rates,â€ Callisto said. â€œBut we need to make sure weâ€™re looking at the economics in a way that encourages new technologies that move the state forward.â€
Callisto said the market for anaerobic digesters should be more stable than that for other renewable sources, such as ethanol, because there are no strong competing markets for the manure product.
â€œI donâ€™t think the pressure is there to get these built just because of federal stimulus money,â€ he said. â€œI think we feel the need to get it right because itâ€™s the right thing to do.â€
McGowan said President Barack Obama is setting a course for renewable energy development, and federal grant money could be used in building new digesters.
â€œWe should take advantage of it,â€ he said, â€œrather than have Wisconsin taxpayers shoulder all of it by themselves.â€
The digesters are a technology worth getting excited about from a construction and environmental standpoint, Taglia said.
â€œI donâ€™t know of any major concerns with digesters,â€ he said. â€œThis is a good energy solution, and Germanyâ€™s been doing this for more than a decade now. Theyâ€™ve produced 1,000 megawatts of energy. Thereâ€™s very credible reasoning to believe this isnâ€™t a passing fad.â€
Hatfield agreed, but said Wisconsin is not Germany.
â€œYou will hear a lot about Europe, but you have to remember their infrastructure is a lot different,â€ he said.
â€œGermany is 60 to 65 million people in a very small area. As we move along the same path here, we have to be mindful about how the rural communities are spread out.
â€œBeing a pioneer in anything means some problems or issues and a pretty big learning curve.â€