LEANTECH: Weapons of Biomass Destruction

By Published On: July 2, 2010

After a decline in the 1990s, the recent expansion of biomass plants has been disappointing in many respects. There also are questions about their impacts on air pollution. In some cases waste is trucked from a long distance, raising concerns as to whether the plants produce more energy than they consume to gather the fuel. California Public Utilities Commission data show the state has 13 biomass plants supplying the state’s investor-owned utilities under renewables portfolio standard contracts. Together their generating capacity is 247.5 MW, with more plants on the way. The state Legislature called for the technology to play a bigger role in providing power to the grid 15 years ago. CPUC data show a 44 MW plant under contract is due to open soon. Three more biomass contracts totaling 27 MW are approved but delayed. Another three contracts totaling more than 77 MW are pending approval. If they all open, it would boost by 60 percent the biomass capacity under contract to the state’s investor-owned utilities. Later this month, Senator Dean Florez (D-Shafter) plans to hold an oversight hearing on a recent San Joaquin Valley Air Pollution Control District decision that was closely related to biomass energy. In 2003, Florez authored a bill calling for an end to open burning on farms to help clean up the polluted San Joaquin Valley. His aim was to have farmers send their waste to cleaner burning biomass energy plants. Now, instead of taking as much agricultural waste as possible--like tree trimmings, nut shells, and other dry farm material--plant operators have preferred to take construction wood waste from urban areas. They get paid more to burn it, according to Florez’s chief of staff Bob Alvarez. While the recessionary downturn caused a dip in construction wood waste and a bit of a spike in agricultural waste burning, the valley’s air district still does not see sufficient biomass plant capacity to end open burning on farms, according to Dave Warner, the agency’s director of permit services. That’s why on May 20 the air district decided to extend exemptions for open burning of many types of agricultural waste past a June 1 date for banning the practice. Florez thinks the exemptions could be tightened up, according to Alvarez. Other folks in the valley are just plain irritated about the decision and the advance of biomass plants, said Tom Frantz, executive director of the Associated of Irritated Residents, a valley clean air and environmental justice group. Frantz questions whether the air wouldn’t be cleaner and the soil richer if a lot of the farm waste was mulched and spread in orchards and fields instead of being burned either in the open or in biomass plants. While cleaner than open burning, Frantz contends that the biomass plants still represent primarily a waste disposal method rather than a source of renewable energy that emits anywhere from seven to 15 times as much pollution as a natural gas power plant, depending upon the pollutant. “The particulate pollution is really bad from these plants,” he said. To make sure the plants are the environmentally optimal way of dealing with biomass waste, he wants policy makers to subject them to “life cycle analysis” similar to the scrutiny the California Air Resources Board gave to transportation fuels like ethanol when it set its low carbon fuel standard. In life cycle analysis, emissions of smog forming pollutants and greenhouse gases, as well as energy use, are examined from the point of production of a fuel or energy source--be it a farm, a mine, or a well--to the point of ultimate use. California Energy Commission renewables portfolio standard program supervisor Kate Zocchetti said that she knows of no such analysis. Instead, she said the state considers biomass a form of renewable energy because lawmakers defined it that way when they enacted the state’s renewable energy legislation, including the renewables portfolio standard law. At the Air Board, which is developing a 33 percent renewable energy standard--upping the state’s current 20 percent standard--the staff has no immediate plans to conduct any life cycle analysis of biomass, according to spokesperson Stanley Young. Instead, he said, the Air Board is planning to “harmonize with the existing renewables portfolio standard program.” If there is a big spike in biomass plants, Young said, the Air Board might scrutinize the technology further, though it doesn’t expect to see much expansion. Current policies clear the way for more biomass plants, which can be considered sources of renewable energy as long as they burn any number of waste materials. These include: agricultural waste, wooden pallets and crates, manufacturing and construction wood waste, lumber mill waste, timber harvested in accordance with state law, and other materials. There are no limits on how far the waste can be trucked, as big California cities run out of places to put solid waste, notes Frantz, who calculates that the average biomass plant needs one big-rig diesel truck delivery a day per megawatt of capacity. He says at least six new plants are proposed in the valley. Frantz, for instance, noted that Liberty Energy wants to build a plant in Kern County that would burn sewage sludge trucked in from Los Angeles to make renewable energy. Current could not reach anybody at the company willing to comment on the plan. If the plan proceeds, Frantz said the proponents can bet that the Association of Irritated Residents will fight it. That’s because, he said, many in the valley are just tired of being “dumped on.”

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