Utah alternative energy supporters joined a nationwide effort Tuesday to promote community opposition to development of new coal-generated power plants and to encourage the pursuit of clean alternative energy sources.

The Tower Theater in Salt Lake City was one of seven sites across Utah and Nevada offering a free screening of a film titled "Fighting Goliath: Texas Coal Wars" that told the story of a group of Texas civic leaders and residents who banded together to fight the proposed construction of 19 conventional coal-fired power plants slated to be built in eastern and central Texas.

The documentary, produced by the Redford Center at the Sundance Preserve, showed that despite strong support from the Texas governor, the activists were able to affect change and reduce the number of proposed facilities from one company, TXU, from 11 to 3.

Opponents said they worried that continued development of coal plants would significantly threaten the air quality in areas where the facilities were built. In addition to the potential health issues, conservationists voiced concern about the financial burden construction of so many plants might put on public resources.

In Salt Lake, local activists said they would prefer seeing those resources put toward development of renewable energy resources such as wind, solar and geothermal. They also talked about working to create jobs and other economic opportunities through the development of a clean-energy economy.

The film was followed by a panel discussion focused on ways to change the nation's current reliance on coal for energy to increased development and use of clean energy such as wind, solar and geothermal technologies.

Some critics of reducing coal use commented in the film that coal and nuclear power, along with hydroelectric energy, are among the few viable, reliable sources of baseload "always on" energy. Proponents of those energy sources also said that continued coal development is needed to meet increasing power demand with alternative energy sources used to supplement that supply.

Clean-energy supporters like Tim Wagner of the Governor's Utah Renewable Energy Task Force countered that argument, saying that one emerging technology under close scrutiny in Utah is concentrated solar power.

He said concentrated solar power plants produce electric power by converting the sun's energy into high-temperature heat using mirrors and that the heat is then sent through a conventional generator.

The plants typically consist of two parts, including one that collects solar energy then converts it to heat and another that converts heat energy to electricity.

"It's the very same process as coal-fired generation, only instead of burning coal to make heat, you're just using the sun," Wagner said.