The University of Texas Austin’s Energy Institute recently published an interactive map that reflects the country’s movement away from coal. It illustrates what kinds of power plants are cheapest to build in every county in the continental United States. For most of the country, the lowest-cost plants are natural gas combined cycle plants (in red), or wind farms (in green). Utility-scale solar photovoltaic plants (in purple) are cheapest in some parts of the West:
The map reflects the fact that natural gas, wind, and solar energy have been the overwhelming majority of electric capacity additions in the country over the past few years. This trend is likely to continue. The Institute also developed a calculator that allows any user to do a side-by-side comparison of two power plants in any given U.S. counties. At this time, the map and the calculator do not yet include the cost of backing up intermittent sources or the effect of federal tax credits for wind and solar. These credits reduce the cost of renewables by about 30 percent. If the map is adjusted for this reduction, wind and solar become the cheapest option in more areas. Coal (in yellow) is only the cheapest option in a few areas. Even in favorable scenarios, coal is still an unattractive option. For example, President-elect Trump repealing President Obama’s climate rules for new coal plants – thereby reducing construction costs for coal from $4,800 per kW to $3,500 per kW – would only have a small effect. It is difficult to imagine a comeback for coal.