Tapping landfills to generate power seemed smart. So why is the industry threatened?

Tapping methane produced from decaying garbage in landfills to generate electricity was among California’s earliest experiments in renewable energy.

But in order to comply with a new regional rule to cut another pollutant — the one that often leaves Southern California blanketed in a layer of smog — a Riverside County landfill has decided to shut down its generators and will simply flare the methane, sending tons of carbon dioxide into the atmosphere.

The decision reflects a clash of environmental goals and regulations — and demonstrates some of the difficult choices confronting California as it pushes ahead on reducing greenhouse gases. Environmental policies on water use and storage, for example, can reduce the amount of hydro power the state will be able to generate.

The regulations are further complicated because climate change programs are largely run by the state’s Air Resources Board, while smog and toxic rules are largely determined by regional agencies like the South Coast Air Quality Management District.

California now has 81 landfills producing electricity, leading the nation. California landfill and composting account for about 9 million tons of greenhouse gas emissions every year, according to state estimates. According to the U.S. Environmental Protection Agency, “reducing methane emissions from municipal solid waste landfills is one of the best ways to achieve a near-term beneficial impact in mitigating global climate change.”

Waste Management’s power plant in Riverside, at the El Sobrante Landfill, generates 3,840 kilowatts of power around the clock — unlike the intermittent output of wind and solar systems. The plant has been operating for about a decade, annually producing enough electricity for a few thousand homes.

The problem began after the AQMD issued a complex 39-page rule requiring that by no later than Jan. 1, landfill methane power plant emissions meet the same standard as other types of engines that use geologic natural gas.

The rule was intended to reduce emissions of oxides of nitrogen, or NOx — considered to be an indirect greenhouse gas since it can affect ozone, but one that is not at the center of climate change efforts.

Read the entire article at LATimes.com