Governors' Wind Energy Coalition

The Department of Energy is making a formal push to develop small, modular coal plants — an idea observers by turns called absurd and wonderful.

In a request for information today, the Office of Fossil Energy said it is seeking input on technical and market considerations to inform development of a small-scale coal generator.

The idea in part is to create a coal-based pilot power plant by 2025 that is small enough to ramp up quickly and provide a backup for intermittent sources like wind and solar. It also could set a path to restart construction of new coal plants — something that has virtually stopped nationwide.

DOE said it’s seeking designs for a highly efficient unit that would be as small as 50 to 100 megawatts, less than half the size of the average coal plant. The generator would not have to capture and store carbon dioxide emissions but must be “capture ready,” according to the agency.

“These plants of the future are envisioned to be modular for lower cost, designed using advanced methods, small scale, highly efficient (greater than 40 percent efficiency), and able to load follow to meet the demands of an evolving electricity grid,” DOE said.

The small coal idea was floated in DOE’s fiscal 2019 budget request earlier this year. At the time, DOE said it wanted to complete at least two designs of advanced “high efficiency” coal units, including small modular ones that have “flexible operating capacity to meet baseload and load following requirements needed for the evolving grid.”

Bloomberg reported earlier this year that coal industry titan Bob Murray called the small coal idea “wonderful.” Murray gave Trump an action plan last year with various ideas to boost coal (Greenwire, Oct. 10, 2017).

Yet many analysts think it is an unworkable idea that could worsen the environment and do little to help the coal industry. For one, there’s not an obvious engineering advantage for ramping up coal versus ramping up gas, they say.

“Physics and engineering pose fundamental operating constraints. Smaller coal units suffer from severe diseconomies of scale that make them relatively inefficient, dirtier and costlier. The only way to achieve DOE’s stated requirements is to have a fundamental breakthrough in combustion technology, which seems unlikely,” said Alex Gilbert, co-founder of SparkLibrary, an energy research company.

DOE is also looking at small modular units for nuclear, but that makes more sense, said Gilbert. Nuclear’s largest expenses are capital costs, and small modular plants could help address that, he said.

“The cost of coal plants, on the other hand, are primarily due to fuel costs. Reducing the size and including modular design will only moderately reduce coal’s capital costs while exacerbating issues that will increase fuel costs,” he said. It also would make it less economical to send rail cars to small modular coal units, according to Gilbert.

The announcement follows multiple efforts by Trump and Energy Secretary Rick Perry to boost the beleaguered coal industry.

The Federal Energy Regulatory Commission rejected DOE’s proposal to compensate coal and nuclear power plants, but the Office of Fossil Energy last year invested $17.4 million in grants to extract rare earth elements, minerals critical to modern technologies, from coal and its byproducts (E&E News PM, Aug. 16, 2017).

Assistant Secretary Steven Winberg, a former coal executive overseeing DOE’s fossil fuel research, last month also told the National Coal Council, a federal industry advisory panel, that modular coal plants were under consideration (Greenwire, April 12). After the information request, DOE could conceivably release a funding opportunity, although it has not been announced yet.

He touted the possibility of American companies taking the small plants overseas, particularly in developing nations where electricity is just coming online.

The goal is to help ensure “coal’s next chapter is as robust as its past,” he said.