Marion considering plasma arc to vaporize trash

The prospect of putting Marion on the front-line of sustainable energy is exciting, City Manager Lon Pluckhahn says, as city leaders consider turning waste into energy with a plasma converter.

The city is reviewing five sustainable-energy proposals and expects to make a decision by August.

“There's no doubt about the technological possibility” of a plasma converter, Pluckhahn said. The question is whether it will be competitive with landfill costs - what the state calls the “method of last resort.”

Plasma converters, sometimes referred to as plasma arcs or plasma torches, use an electric arc much like lightning to create high temperatures that virtually destroy waste and convert it to gases and inert materials that can be used to make useful products. It's all done using part of the energy from the waste; the rest is used to provide steam, natural gas, biodiesel, methanol or electricity.

Charlie Kress of Marion, a retired engineer working with Waste Not Iowa, has been pushing the idea of developing a plasma converter for at least five years and said it's time to act.

“Plasma's day has arrived,” Kress said. “From an environmental and engineering standpoint, it's not questionable. Now we have to show it makes economic sense.”

With the city reviewing proposals from four firms for developing a plasma converter, Kress said his hopes have never been higher.

“This offers a big opportunity to harvest a lot of energy from our garbage,” Kress said, adding that more energy is being landfilled than is available from wind and solar combined.

P. Ferman Milster shares Kress' hope for plasma converters but isn't ready to dive headlong into the technology.

“This could easily be a 50-plus-year decision,” said Milster, associate director of utilities and energy management at the University of Iowa. He's been involved in discussions in Marion and sees possibilities for developing a plasma converter at the university.

Still, “I don't want to be rolling over in my grave, because people are so mad at me for committing the university to plasma arc,” he said.

Developing a plasma converter in Marion would be a big economic stimulus, Pluckhahn said. He estimates a plasma converter would carry a $150 million-plus price tag, create 400 construction jobs and 40 permanent jobs and increase the city's property tax base by 10 percent.

It's far from a done deal, however. Among the questions to be answered are whether it should be small enough to handle only local solid waste or big enough to serve several counties. Then there's the question of what form of energy to produce: steam, electricity, biodiesel or a variety of gases.

Although it would be privately owned, Pluckhahn sees a role for the city as a funding partner or, perhaps, an equity partner, with access to grants and loans from government sources interested in developing sustainable energy.

The UI could play a similar role, added Milster.

“The university is interested in partners with deep technological and financial pockets,” he said. “There's an inherent risk being on the leading edge of a new technology, so we'll go very cautiously.”

Like Marion, Milster said, the university has a stewardship role. “We're using other people's money.”

Pluckhahn expects the review process to take as long as six weeks. A committee including representatives of the council, Waste Not Iowa and possibly an outside consultant are meeting with the firms before making recommendations.

UI may also consider plasma arc

The University of Iowa burns 90,000 tons of coal each year, and the money spent on it all goes out of state. Coal accounts for more than half of UI energy use on the main campus. So local sustainable energy is attractive.

That's one reason P. Ferman Milster, associate director of utilities and energy management at UI, is participating in Marion's discussion of developing a plasma converter. Plasma technology “is an opportunity to get our fuel locally and stimulate the local economy,” said Milster, who adds that the UI spends nearly $20 million a year on purchased power.

A plasma converter could be used to meet UI's 24/7 demand for steam, he said.