One of the advantages of electric cars is that they get cleaner as the emissions associated with generating the electricity to power them decrease.
And the good news for electric-car drivers is that the grids that supply their electricity have been getting cleaner--and will likely continue to do so this year and into the future.
Coal's share of the electricity-generating load is gradually being eroded by cleaner alternatives.
MORE: In Just One Year, Electric Cars Have Gotten Cleaner: How'd They Do That? (Dec 2014)
Natural gas is already cheaper than coal and quite abundant, while technological advances and public pressure to cut emissions are allowing wind and solar generation to increase market share.
That's the trend described in 2015 grid-mix projections from the U.S. Energy Information Administration (EIA).
A major highlight of those projections is that 91 percent of an expected 20 gigawatts of new generating capacity will come from wind, solar, and natural gas, according to a Navigant Research blog post.
Natural gas flaring from oil well [licensed under Creative Commons from Flickr user Sirdle]
The EIA anticipates 9.3 GW of new wind generating capacity, 6.3 GW of natural gas, and 2.2 GW of solar.
Meanwhile, no new coal power plants are scheduled to come online this year, while 12.9 GW of coal generation capacity and 1.98 GW of natural gas will be retired.
RELATED: Natural Gas Continues To Replace Coal: 'Bridge' Fuel To Lower-Carbon Energy
Extensive use of natural gas helps reduce emissions, but the significant increase in wind generation predicted by the EIA could forecast broader changes.
According to previous EIA estimates, the U.S. is already the world's largest consumer of natural gas, and could see a 33-percent increase in demand by 2040.
Photovoltaic solar power field at Volkswagen plant in Chattanooga, Tennessee
Yet while natural gas can rely on existing infrastructure, similarly-large increases in wind or solar consumption could change the shape of U.S. energy infrastructure.
Renewable energy sources are expected to promote distributed generation--lessening reliance on the grid.
ALSO SEE: What Future For Coal In The U.S.: Slow Decline Or Faster Retreat?
Utility companies are already concerned about how this will effect their business model, to the point of pressuring state governments to curb home solar development through legislation.
So while the sources of electricity may change, shifts in the method of distribution could be just as significant for the energy industry.