As more plug-in electric cars hit the road, the infrastructure used to generate electricity will need to be increasingly scrutinized.
The most straightforward way to get cleaner electricity is to switch to a less-polluting source like natural gas--or better yet, renewable sources like wind and solar.
Yet in the United States coal is still cheap and plentiful, and utility companies that use the fossil fuel likely won't be eager to switch.
One company has moved beyond studies to build a plant with a goal long-sought by fossil-fuel advocates: capture the carbon dioxide emitted by a coal power plant.
Mississippi Power plans to open a plant designed to capture 65 percent of its carbon emissions in 2016, but this "clean coal" solution may not be all its cracked up to be, according to a lengthy and thorough report by Grist.
Two BNSF locomotives hauling coal trains meet near Wichita Falls, Texas
Rather than simply burn coal, the plant uses a gasification process that allows it to take advantage of the lower-quality lignite coal that's abundant near its location in Kemper County, Mississippi.
It also means the plant could be more easily outfitted with carbon capture and sequestration (CCS) equipment--which captures carbon and stores it for later transport offsite.
Research on CCS has been ongoing for decades, and a coal plant in Saskatchewan, Canada, was retrofitted with CCS equipment in 2014.
However, the Mississippi plant will be the first commercial experiment with the technology in the U.S., and that's got some politicians and analysts excited.
In 2010, Secretary of Energy Steven Chu wrote a letter to the Mississippi Public Service Commission urging it to the back the project.
Two years earlier the state legislature passed the Baseload Act--which allows Mississippi Power to raise customers' rates to fund the project.
Electric power plant outside Ithaca, New York
This has led to major rate hikes for many customers in one of the poorest parts of the country.
Some Kemper County residents feel they are being shortchanged by the utility on wages for jobs in plant construction.
They also complain about the price being offered by Mississippi Power--a division of national utility Southern Company--for land it hopes to acquire for the plant and an adjacent coal mine.
Meanwhile, the costs of the carbon-capturing plant have ballooned from an original estimate of $1.8 billion in 2009 to $6.2 billion last year.
All of this is supposed to yield a plant with carbon emissions comparable to a "similarly-sized natural gas plant," according to Mississippi Power.
That should come with an asterisk, though.
Capturing carbon requires extra energy--which in turn means burning more coal. An extra 20 to 30 percent more coal, according to recent estimates.
Oil well (photo by John Hill)
An integral part of the plant's financial plan is reportedly to use that carbon for "enhanced oil recovery"--forcing more oil out of old wells.
Nonetheless, Southern Company has already formed an alliance with some of China's biggest energy providers to build similar plants.
There are currently five more CCS plants on the way for China, plus six in Europe, and two in the U.S.