Tag: Nicholas School of the Environment

EPA’s proposed limits on power plant emissions would accelerate shift from coal to natural gas

Coal-fired power plants currently produce about 46 percent of the country’s electricity. Photo via Wikipedia and the Creative Commons.

Study compares economic sensitivity of gas and coal-fired power plants

By Summit Voice

SUMMIT COUNTY — Proposed new limits on power plant emissions could spur a big shift away from coal and toward natural gas. The new rules on sulfur dioxide, particulate matter, nitrogen oxide and mercury may make nearly two-thirds of the nation’s coal-fired power plants as expensive to run as plants powered by natural gas, according to a new Duke University study.

“Because of the cost of upgrading plants to meet the EPA‘s pending emissions regulations and its stricter enforcement of current regulations, natural gas plants would become cost-competitive with a majority of coal plants — even if natural gas becomes more than four times as expensive as coal,” said Lincoln F. Pratson, a professor of earth and ocean sciences at Duke’s Nicholas School of the Environment. Continue reading “EPA’s proposed limits on power plant emissions would accelerate shift from coal to natural gas”


Large-scale forest bio-energy creates carbon debt

Study says nurturing healthy forests does more to curb global warming

Healthy, growing forests are good carbon sinks; converting woody biomass to energy results in a carbon debt that takes 100 years to repay.

By Summit Voice

SUMMIT COUNTY — While some logging advocates continue to talk up forest biomass as a green energy source, there’s good reason it isn’t happening on a significant scale. Cutting wood and burning live trees, in whatever form, is just not energy efficient, except perhaps on a modest scale with low-frequency harvests every 50 to 100 years — or on a small, local level, where already dead wood is converted fuel on the spot.

In one of the most recent studies, researchers at Duke and Oregon State universities concluded that maintaining intact forests as carbon sinks does more to curb climate change over the next century than cutting and burning their wood as fuel.

After modeling numerous harvesting and conversion scenarios, the study concluded that it takes more 100 years to repay the carbon debt — the net reduction in carbon storage — incurred by cutting, transporting and burning woody forest biomass. Continue reading “Large-scale forest bio-energy creates carbon debt”

Global warming: Forests not adapting as predicted

Can forests adapt to global warming?

Study shows no northward migration as warm zones expand northward

By Summit Voice

SUMMIT COUNTY — Trees in the eastern U.S. are not adapting to global warming as quickly as expected, according to a team of Duke University scientists who looked at scores of species to try learn how they’re adapting to a changing climate.

“Warm zones have shifted northward by up to 100 kilometers in some parts of the eastern United States, but our results do not inspire confidence that tree populations are tracking those changes,” said James S. Clark, H.L. Blomquist Professor of Environment at Duke’s Nicholas School of the Environment. “This increases the risk of serious lags in tree migrations.”

“Many models have suggested that trees will migrate rapidly to higher latitudes and elevations in response to warming temperatures, but evidence for a consistent, climate-driven northward migration is essentially absent in this large analysis,” Clark said. Continue reading “Global warming: Forests not adapting as predicted”