A Harvard Medical School study, published in the Annals of the New York Academy of Sciences, found that the extra health and environmental costs of burning coal in the US costs the country up to $500 billion a year, or 9 to 27 cents per kilowatt-hour (kWh) of electricity.

Each stage in the life cycle of coal—extraction, transport, processing, and combustion—generates a waste stream and carries multiple hazards for health and the environment. These costs are external to the coal industry and are thus often considered “externalities.” We estimate that the life cycle effects of coal and the waste stream generated are costing the U.S. public a third to over one-half of a trillion dollars annually. Many of these so-called externalities are, moreover, cumulative. Accounting for the damages conservatively doubles to triples the price of electricity from coal per kWh generated, making wind, solar, and other forms of nonfossil fuel power generation, along with investments in efficiency and electricity conservation methods, economically competitive. We focus on Appalachia, though coal is mined in other regions of the United States and is burned throughout the world.

The full report can be downloaded here: Full cost accounting for the life cycle of coal