Southern California utility companies say they want to offer their customers what they say is a greener option for natural gas. The gas comes from some unlikely sources: wastewater treatment plants, dairy farms and landfills.
All those sites are rich in organic waste. When it decomposes, the waste produces methane, which can be purified and used like traditional gas to heat homes, fuel vehicles and for cooking.
"This is using a product that would ordinarily be wasted," said Frank Mazanec with BioFuels Energy, LLC, a company that turns wastewater into gas at the Point Loma Waste Water Treatment Facility. "It's sludge being contributed every day, so it's renewable in that regard, so this gas is being produced, treated and used where it would otherwise be going into the atmosphere and be wasted."
San Diego Gas and Electric and Southern California Gas Company are looking to replicate the Biofuels process and offer the gas to residents as soon as next year.
"We think renewable natural gas is part of the solution to meeting our state's ambitious climate goals. Whether that be through solar or wind, renewable natural gas we see as one piece of the pie to accomplishing those goals," said Joe Britton, a spokesperson for SDG&E.
California law requires the state to reduce greenhouse gas emissions to 1990 levels by 2020. According to the California Air Resources Board, 80 percent of methane emissions in California come from waste sources like landfills, wastewater treatment plants and dairy farms. Methane is among the worst greenhouse gases. SDG&E says if it wasn't captured from these waste sources, it would be released into the environment and would contribute to global warming.
"All that renewable natural gas is, it's effectively methane, just like the natural gas that you get from a fossil fuel source, so by taking that renewable gas and putting it into our existing pipeline, we are replacing fossil fuels," Britton said.
But not everyone thinks this is a good solution for the environment. Rachel Golden of the Sierra Club said that while getting rid of methane from waste sites is important, "once it is in the pipeline, it's basically equivalent to fossil gas. It's going to have the same safety risks as when an earthquake hits and the pipes shake, that can lead to fires and further leakage. It's going to have the same safety risks, the same air pollution, the same methane leakage risks, the only difference is that the source is different."
Golden said using any kind of gas isn't a sustainable or environmentally friendly option.
"The other option that the gas industry doesn’t like to talk about is electrification and that basically means replacing our gas combustion appliances with super-efficient modern electric technology that can save us on our energy bills, improves indoor air quality and is far better for the climate," she said. "It can be powered by local clean energy. We need to stop looking at these two gas combustion based options and look at the electrification option."
SDG&E disagrees and hopes its proposed program might help build demand for natural gas in California. The California Public Utilities Commission has to approve the program. SDG&E say after that happens and based on demand, they will be able to set the rates for the renewable gas for consumers.
