PORTLAND, Maine — It just so happens that climate-changing carbon dioxide, worked up to a semi-liquid state, could play a part in reducing emissions of its gaseous counterpart and helping to solve New England’s energy challenges.
And it could create a range of new jobs in Maine, too.
David Stapp, president of the Wiscasset-based Peregrine Turbine Technologies, said the properties of carbon dioxide in a “supercritical” state — and its suitability for propelling a turbine — aren’t new.
But the circular system his company is developing for heating that supercritical carbon dioxide could be the new take on an old technology that helps power generators adapt to changing demands, in New England and elsewhere, regardless of fuel source.
“It doesn’t care what you’re burning in there to create the heat, and that opens a whole range of technologies,” Stapp said. “We can burn things that others could only dream of.”
Biomass, coal, poultry waste, whatever. The system also uses heat exchangers to recapture heat from the supercritical carbon dioxide after it passes through the turbine, cooling it again and reusing the heat for another go-round. The company estimates the turbine will be 30 percent to 60 percent more efficient than existing steam units.
“We’re coming into the marketplace at just the right time,” Stapp said. “There’s a real need for energy innovation.”
The first systems it plans to use would be fired by natural gas and target distributed generation applications, where the power generators are located near end users rather than at central power plants.
Stapp, a former engineer with GE Aircraft Engines, said a recent study in the Waterville area estimated the region could be served with about 9 megawatts of generation capacity, an amount that could be mostly fulfilled by one of its 6 megawatt turbines.
In power plants, he said, multiple turbines would run on parallel schedules to allow some to come offline for maintenance while others are available to generate power to the grid.
New England’s energy needs are particularly acute. A recent report by the Portland firm La Capra Associates, commissioned by the American Petroleum Institute and America’s Natural Gas Alliance, estimated that New England businesses will pay a $5.4 billion premium on energy if natural gas pipelines and electricity transmission infrastructure aren’t upgraded.
And coal generators — sparse in Maine — could face further challenges to their efficiency if the emissions reduction requirements of the embattled federal Clean Power Plan are put into effect.
“If you have a coal plant right now you’re in a cold sweat looking for something to rescue you, and this is the kind of thing that could do it,” Stapp said.
That “could” means somewhere in the ballpark of three years more research and development to get the first Peregrine turbine connected to the grid and generating power.
Last month, the company signed onto a government research partnership that will help it do just that.
Something to prove
Sandia National Laboratories in Albuquerque, New Mexico, last month signed an agreement with Peregrine and other related companies to help advance research into using supercritical carbon dioxide to power a turbine using heat from burning fossil fuels.
The pilot system tested at Sandia’s Brayton Lab will be based on Peregrine’s design for a six-megawatt engine. The company has not yet built any test models of its design.
Gary Rochau, manager of Sandia’s Advanced Nuclear Concepts Department, said in an announcement of the agreement that it’s the first major collaboration with private industry “that will take the Department of Energy’s lab-scale technology and accelerate its development to commercial industry deployment of a highly efficient, low carbon emission, electrical power generator.”
Stapp said the testing agreement with Sandia doesn’t change the private investor-backed company’s expectation for selling its turbine to power generators, but it will help make the turbine system more bulletproof for an application that requires reliability.
“They’ll bring expertise in testing and test facility design as well as data interpretation,” Stapp said.
While the testing phase aims to prove the technology in a laboratory, Stapp said the company founded in 2011 is under pressure from investors to start generating revenue, too.
“Our company has been fully funded by private investors,” Stapp said. “It’s not a [Department of Energy]-funded operation and so our need to drive to commercialization is a real one.”
Stapp said the company has raised $6.4 million — $5.4 million in equity and $1 million in debt — and recently opened another equity round to raise $4.5 million.
The company’s also applied for a loan of up to $500,000 from the Maine Technology Institute to fund testing of a 1/13th-scale model of the full 14-foot-tall and 25-foot-long turbine. Stapp said the company also is negotiating with Sandia on another agreement that would allow the lab to use some Department of Energy funds for development.
What’s in it for Maine?
In preparation for its pitch to the Maine Technology Institute, Peregrine estimated that getting its turbines grid-connected by 2018 could by 2020 create or benefit about 760 jobs up and down the supply chain. About half of those, the company estimated, would be in Maine.
That includes new work for industries such as biomass power generation, which has relied in large part on higher prices for power generated, through renewable energy credits.
Stapp said he expects the increased efficiency of the company’s turbine to allow biomass generators to compete directly with natural gas generation on price, and at the same time create a market for tree tops and limbs that might not be used otherwise.
“There’s a huge potential with a native fuel source that wouldn’t have to be piped or trucked in anywhere,” Stapp said.
Stapp said he and his business partner Bob Brooks “are both committed to seeing this become the technology or innovation anchor for the state of Maine and that it drives jobs in both technology and manufacturing.”
The company now employs about 10 people directly and under contract, Stapp said, including some recent graduates from the University of Maine’s mechanical engineering department and interns from the University of Southern Maine.
“We’re putting our money where our mouth is and hiring young engineers straight out of Maine schools who want to stay in state,” Stapp said.