Specialists say wind and coal don't mix; Natural gas favored as a backup source of power for Delaware
It doesn’t make sense to back up a wind farm with a coal gasification plant, energy specialists said.
Last week, Gov. Ruth Ann Minner suggested that one answer to the state’s long-term electricity needs could be a new NRG coal gasification plant at Indian River, combined with an offshore wind farm.
After electric bills increased by 59 percent last year, lawmakers ordered state agencies to look for homegrown sources of power to stabilize prices.
Minner made her comments after the Public Service Commission voted to pursue an offshore wind farm, backed up by a small fossil fuel plant somewhere in Sussex County. The backup plant would provide power on days when the wind was light.
A natural gas plant is suited for that backup role, said Dave Bayless, a professor of mechanical engineering at Ohio University.
A natural gas plant is able to fire up quickly, but a coal gasification plant starts up more slowly, he said. That means a coal plant used as a backup would be less responsive during peak demand periods, he said.
A coal gasification plant, while cleaner than a traditional coal plant, sends plenty of pollutants into the atmosphere upon startup and shutdown, he said.
“That would be the worst possible thing to do with IGCC,” Bayless said, referring to coal gasification, also called integrated gasification combined cycle technology. “If you want a backup, use natural gas.”
Robert Howatt, public utilities analyst for the Public Service Commission, agreed that natural gas has a quicker reaction time. Scaling down NRG’s proposed 600-megawatt coal gasification plant to a backup unit “represents some real challenges and is unlikely.”
NRG spokeswoman Lori Neuman said coal gasification can serve as a backup, but did not elaborate.
Coal gasification is looked at more as a provider of baseload energy, said Nick DiPasquale, conservation chairman of Delaware Audubon.
“Arguably, an IGCC plant would be an improvement over traditional pulverized coal plants,” but under even the most optimistic scenarios, “it will contribute millions of tons of additional carbon to the atmosphere and will do so for the next 50 years.”
DiPasquale was referring to one of NRG’s plans, which includes capturing 65 percent of the carbon dioxide and injecting it nearly a mile underground.
By Aaron Nathans
The News Journal
16 May 2007
|Wind Watch relies entirely
on User Funding