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Powering the campus

All eyes are on Duke Energy’s CHP strategy

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william schlesinger
President Emeritus, Biogeochemist

On whichever side on the aisle you sit, there are a few basic facts established by careful scientific measurements over the past few decades: the Earth is getting warmer, the concentration of carbon dioxide in the atmosphere is rising, and carbon dioxide absorbs heat radiating from the Earth’s surface. The geologic record shows us strong correlations between high CO2 in the atmosphere and warm epochs in the Earth’s past. No amount of political rhetoric can change these observations.

Climate change is not a national, but rather a global, problem, wrought by our use of fossil fuels to power our economy. For the United States, the spirit of EPA’s regulations for large power plants—the Clean Power Plan—was to curb our nation’s emissions of carbon dioxide to the atmosphere, in hopes of mitigating the full extent of ongoing climate change. Other nations have other approaches, but they look to us for leadership, as one of the leading sources of CO2 emissions.     

For the first round of reductions in the Clean Power Plan, power plants less than 25 megawatts were exempt from regulation in an attempt to ease the burden on small-source generation. However, in North Carolina, Duke Energy has responded by abusing this loophole, proposing to build a host of new small power plants, each about 20 MW, including one in cooperation with Duke University to provide power to its campus in Durham. This new plant would be gas-fired, providing a combination of heat and power—a CHP facility.

The project is anticipated to lower the emissions of carbon dioxide that might be expected from Duke Energy’s existing grid of large coal-fired power plants, but there is no provision that guarantees that any of the existing generation capacity will be retired. The University claims that CHP will increase its overall energy efficiency by eliminating separate facilities for heat and power. With natural gas at historically low prices, the switch will save money as well—at least as long as gas prices remain low.

Natural gas is often touted as an ideal fuel to bridge the transition of society to a future world of non-fossil energy, when fossil fuels are depleted and expensive and we begin to take climate change seriously. Of course, natural gas itself is a fossil fuel, which emits carbon dioxide when it is burned. A certain fraction of the natural gas—largely methane—that is supplied to power plants inevitably leaks to the atmosphere. Current global estimates suggest the leak rate is about two percent of production. Importantly, any leak rate above about one percent of production negates most of the benefit of natural gas on mitigating climate change, because methane itself is a greenhouse gas that contributes to global warming.

With the international acceptance of the Paris Climate Accord, we are moving along a societal pathway that is free of fossil carbon emissions, avoiding the huge costs of sea level rise, reduced agricultural productivity, and enhanced spread of infectious diseases, which are all associated with global warming. At the same time, we must not live in the dark.

Spending $55 million on a CHP plant will implant major, long-lasting infrastructure that is certain to delay this transition of utilities to non-emitting, renewable energy sources such as solar and wind. Across the nation, the large utilities that supply electricity to the grid have been loath to accept distributed generation, such as solar, that threatens their monopoly.  Coupled with new battery technology, solar could offer an uninterrupted power source for a large university, providing an example of how the world must work in the future.

Those looking to institutions of higher education for leadership will look carefully at how Duke University responds to this proposal. And utilities across the nation will look carefully at Duke Energy’s strategy to duck under the threshold of regulation with separate, small power plants.

Renewable energy is the way; not skirting under the bar of EPA regulations with an array of small power plants that maintain the old ways of doing business. Setting an example for others, a solar-powered campus would light the way for bright young minds of the next generation.

 

Adapted from an op-ed originally appearing in the (Raleigh) News and Observer, 22 November 2016

william schlesinger
President Emeritus, Biogeochemist

William Schlesinger is active in communicating science to policy makers and media. He has testified about environmental issues in Congress and in state houses, and has been featured in media including NOVA, the Weather Channel, Discover, National Geographic, and the New York Times.

He discusses a range of environmental issues in his weekly blog, Translational Ecology.

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