From coal mines to switchgrass

Cape Breton, Nova Scotia, is shifting its shuttered coal mines into test beds for future alternative fuels, launching a program to grow switchgrass on the site of the former Broughton coal mine and pelletizing the grass for use in home heating stoves.

The $300,000, three-year project is part of a larger Canadian initiative called Green Mines-Green Energy to clean up and re-use the now-marginal land for sustainable energy.

The Cape Breton Development Corporation, known as Devco, a Crown corporation, is leading the switchgrass project on Cape Breton Island in a joint venture with the Canada Centre for Mineral and Energy Technology, a network of energy and mining laboratories managed by Natural Resources Canada.

Devco was established in 1967 to rehabilitate what was once a booming coal mining region, but is now charged with the sale and environmental remediation of the underground mine sites, the last of which closed in the fall of 2001. There's still some small-scale surface mine production in the area, but most of the country's coal is now imported.

In addition to switchgrass, the corporation is looking into using geothermal technology to tap the mine water in the region, as well large-scale coal-bed methane projects.

"We are basically being catalysts," Gerard Shaw, manager of safety and security at Devco, told the Cleantech Group. "We want to start the projects, we want to generate interest in all of these projects."

"And then we would hope that, and would expect that, local business groups or industry would take the initiative to take over some of these properties that could grow switchgrass, and become a commercialized venture or a small business venture for local farmers or entrepreneurs."

The pellets are very similar to the wood pellets available today, but a special stove is needed because of the sticky residual from the potassium in the switchgrass. But Shaw said the switchgrass pellets burn a little cleaner and have a better energy output than wood.

Switchgrass has also been looked at as a feedstock for use in next generation biofuels, since it can be grown on marginal land and does not double as a food crop. According to a study backed by the U.S. Department of Agriculture and the U.S. Department of Energy, switchgrass yields about five times more energy than it takes to grow it (see Switchgrass gets high marks in new study).

Devco is working with the Atlantic Coastal Action Program—Cape Breton, a non-profit group that promotes sustainable communities, on setting up and planting the grass, which is expected to cover four plots on a small portion of the 10 to 12 acre site.

"It's a pretty desolate, gray site. Nothing really growing there," said Eleanor Anderson, executive director of the non-profit group.

The Broughton coal mine closed down operations about 60 years ago, but is still covered in waste rock and coal depositions.

The Atlantic Coastal Action group is still working on the plots, bringing in organic compost from Antigonish, Nova Scotia, made up mostly of lobster and crab shells, but they should have some signs of growth soon.

"We'll certainly know if it's taking, whether it's growing or not this fall," said Anderson.

Cape Breton University is leading the research on the project, which will monitor the growth of the switchgrass.

"Right now we're looking at the viability of growing the crop first," she said. The Broughton site is the first location to get a green energy test project, but Anderson said there are multiple sites that could be used in the initiative.

The industry is still in the early stages on the pelletizing process for switchgrass, according to Shaw, but there could some other benefits to the Cape Breton switchgrass in the meantime.

"If it could be used as a remediation technique as well, as well as just growing on marginal lands, that's part of the research as well," he said. "To see if the compost and the switchgrass will stop the percolation of water and oxygen into the waste rock and stop the generation of acid mine drainage."

"So it may have a multifold purpose."

Over the next decade, Devco plans to sell or transfer its remaining 585 properties, covering approximately 5,500 acres.

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