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Hybrid Solar-Coal Plant: Excuse to Pollute?

Colorado demonstration project slightly increases 53-year-old plant's efficiency.

2 min read
Hybrid Solar-Coal Plant: Excuse to Pollute?

Utility company Xcel Energy recently announced that the first ever demonstration of a hybrid solar-coal power generating station is up and running near Grand Junction, Colorado. The plant uses an array of concentrating solar parabolic troughs to reduce the coal consumption of unit 2 of the Cameo coal power station.

An interesting idea, to be sure, but the scale of the coal issue makes this seem like little more than lipstick on a pig. A very, very dirty pig. As NASA scientist and leading climate expert James Hansen writes in his recent book Storms of My Grandchildren, "If we want to solve the climate problem, we must phase out coal emissions. Period."

Hansen and others have shown [PDF] that only if global coal emissions are completely phased out by 2030 could atmospheric concentrations of carbon dioxide be stabilized at between 400 and 425 ppm (which certainly seems unlikely from our current level of about 392 ppm), most likely averting some of the more dire climate scenarios. The US currently gets about half of its electricity generation from coal; we better get started if we want that 2030 target to be remotely realistic.

Xcel's demonstration project - built along with Abengoa Solar - could reduce coal use at the Cameo generating station by two to three percent, and according to a video the company produced, scaling up the idea could someday bring that to 10 percent. If we take Hansen's - and many other scientists' - word for it, 10 percent reductions in coal use over the next decade or so isn't nearly enough.

That's not to say this isn't better than nothing. It just seems that the $4.5 million price tag might have seen better use in other renewable projects rather than a slick way to keep a 53-year-old coal plant open far into the coming renewable energy age.

"We are very excited about getting this unique renewable energy project on line," said Kent Larson, vice president of Xcel Energy, in a press release. "If this project produces the successful results we expect, this type of solar thermal integration will help move the use of solar energy one step closer to being a potential technology for improving the environmental performance of coal-fired power plants for Xcel Energy and for utilities around the country."

The key there is that the aim is to improve coal plants' performance. When faced with the realities of coal mining and emissions, though, most of us might prefer to just get rid of them.

(Images via Sandia National Laboratory and Xcel Energy)

The Conversation (0)
This photograph shows a car with the words “We Drive Solar” on the door, connected to a charging station. A windmill can be seen in the background.

The Dutch city of Utrecht is embracing vehicle-to-grid technology, an example of which is shown here—an EV connected to a bidirectional charger. The historic Rijn en Zon windmill provides a fitting background for this scene.

We Drive Solar

Hundreds of charging stations for electric vehicles dot Utrecht’s urban landscape in the Netherlands like little electric mushrooms. Unlike those you may have grown accustomed to seeing, many of these stations don’t just charge electric cars—they can also send power from vehicle batteries to the local utility grid for use by homes and businesses.

Debates over the feasibility and value of such vehicle-to-grid technology go back decades. Those arguments are not yet settled. But big automakers like Volkswagen, Nissan, and Hyundai have moved to produce the kinds of cars that can use such bidirectional chargers—alongside similar vehicle-to-home technology, whereby your car can power your house, say, during a blackout, as promoted by Ford with its new F-150 Lightning. Given the rapid uptake of electric vehicles, many people are thinking hard about how to make the best use of all that rolling battery power.

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