An increasingly vocal, potent, and widespread anti-coal movement in the West is making for some unusual partners. Environmental groups that have long opposed new power plants are being joined by ranchers, farmers, retired homeowners, ski resort operators, and even religious groups.

Activists say the increasing diversity of these coalitions is making them more effective. Power companies concede that anti-coal coalitions are indeed becoming more effective—and they describe that as a threat to the reliability of the nation’s electric grid. In their view, building more coal-burning power plants is the most realistic way to meet the rising demand for electric power.

The collaboration of former strangers—even enemies in some cases—to fight coal development is largely a Western phenomenon. While medical groups, city officials, environmental groups, and others have banded together to fight coal plants near cities east of the Mississippi, the power plants in the West are largely in rural areas and thus directly affect farmers and ranchers living on the plains, the prairies, and near the Rocky Mountains.

But government projections suggest that coal, which provides 50 percent of the nation’s electricity and a quarter of its total energy, will continue to dominate the nation’s energy mix, despite its environmental problems. As of last May, the Energy Department projected that 151 coal-fired plants could be built by 2030 to meet a 40 percent rise in demand for electricity, largely from soaring populations in Western states.

Still, opponents of coal plants are winning some battles. Reports from the government, the industry and environmental groups show that at least three dozen coal plants have been canceled or scaled back in the last two years.

For many farmers and ranchers, their aversion to coal is more pragmatic than philosophical. Their crops and livestock have been plagued by severe droughts and storms lately, and some wonder whether those are linked to global warming. Whether that proves to be the case, the strain on their finances has made them more interested in renewable-energy projects, like wind turbines, on their land.