Local governments have been spending hundreds of millions of dollars in expanding, and planning new waste-to-energy plants. The recent rise comes in response to growing landfill costs and uncertain energy prices down the road.

One incinerator in Florida completed a $120 million plan to expand its capacity by 50 percent. Another expansion in Florida, and two others in Minnesota and Pennsylvania are in the works too. There are currently at least a dozen proposals for the creation or expansion of new plants across the U.S.

The waste-to-energy business, such as the one pictured above in Warwick, U.K., is on the rise.

The process begins by feeding the refuse into a chamber where it is set afire by natural gas. Heat from the fire creates steam that turns a turbine which produces electricity.

The incinerator business had seen hard times since the mid-90’s, when they were overrun by pressure from various environmental groups. The groups complained about the toxic emissions and mercury levels contained in the ash.

But lately it seems to be back in full swing.

While most businesses struggled at the time that gas prices were skyrocketing, the incinerators began to make its comeback. Trucking the refuse to distant landfills became a lot more expensive than in previous years. At the same time, the greater demand for electricity and renewable-energy credits made the power generated at these plants more valuable.

“People recognize that waste to energy has worked, and the waste stream is growing,” said Dave Vollero, executive director of Pennsylvania’s York County Solid Waste Authority. He’s planning a $175 million project that will boost capacity at his facility by 50%, according to the Wall Street Journal.