Conference: Switching from black to green

By Lisa Gibson
Posted January 14, 2010, at 4:02 p.m. CST

The paradigm shift in converting a coal power plant to biomass is riddled with permitting hurdles, along with technology and logistics issues.

"Going from a black hat to a green hat is hard to do," said Mike Hawkins, president and CEO of Ohio-based Red Hawk Energy LLC, who participated in a panel titled �Rightsizing and �Right siting' Biomass Power in the Pacific West at the Pacific West Biomass Conference & Expo in Sacramento. The company's 52 megawatt coal plant is transitioning to biomass power and should be fully operational with 100 percent biomass in the second quarter of 2011, he said.

In converting, economics of size matter, he said, reiterating the point made by fellow presenter Peter Flynn, a professor in the Mechanical Engineering department at the University of Alberta. Flynn addressed attendees with his presentation Small is not Beautiful. Optimal plant size varies with biomass feedstock availability and processing technology, but is much larger than conventional wisdom suggests, he said. Although larger plants may have longer transportation routes, efficiency in larger plants comes out on top. "Capitol efficiency trumps transportation costs," he said.

In large power plants, coal costs about $4,500 per kilowatt hour, with biomass at about $4,000, depending on the plant size, Hawkins said. Converting a coal plant to biomass, however, costs only $1,000 per kilowatt hour.

Conversion is a challenging development project that should not be underestimated, Hawkins said. Operating issues included fuel quality, erosion and corrosion, the capacity factor, operations training and fuel handling. Technology issues included a boiler study, unit de-rating, boiler and fuel feed modifications, and fuel receiving and storage. Companies can opt for a basic dump truck and storage system, or take the route Red Hawk Energy took: a state-of-the-art storage facility with dust and fire suppression, Hawkins said.

The plant is currently co-firing 20 percent biomass. "It's all about the fuel," he said. He recommends plants considering conversion perform a detailed fuel study, and analyze the reliability of suppliers and fuel contracts. "It's a whole different ball game than what we've been used to in the past," he said.
Hawkins also discussed power purchase agreements, emphasizing the importance of obtaining the terms needed. "This is really the gift that keeps on giving," he said.

Other issues companies will face include lender issues and development and construction costs. The entire process from start to finish probably will take about three years, said Hawkins, who used a tortoise in his presentation to illustrate the slow permitting process.

"California is a national leader in renewable energy, but also in regulatory complexity, uncertainty and confusion," said Frederick Tornatore, chief technical officer of California-based TSS Consultants. He discussed the "four Ps" of the permitting process: planning, perception, perseverance and patience. "There's no such thing as fast-track permitting," he said.

But it is possible and more plants can be built. Black & Veatch, a global consulting, engineering and construction company, conducted a study assessing all renewable resources in California, identifying where transmission lines would need to be, according to speaker Scott Olson, senior consultant with the company. Black & Veatch based its analysis on several criteria. The study identified a potential 46 projects, for a total of 1,725 megawatts. "The economy of scale is absolutely true," he said.