美国 谷神星公司., which develops and markets high-yielding energy crops for cellulosic ethanol production and biopower, announced that switchgrass can produce substantially more biomass than previously reported. Additionally, average yields — used to forecast bioenergy economics and environmental benefits — could be far too conservative.
Yield results from Ceres’ nation-wide network of field trials showed that average biomass yields among last season’s switchgrass tests were as high as 50% over the government’s projected yields for 2022.
California reported the highest yield, where a Ceres experimental variety produced 19 tons per acre. Proprietary varieties sold under the company’s Blade Energy Crops brand were consistently the highest yielding varieties across multiple trial locations, with average yields nearly 10 tons. Ceres switchgrass product manager Cory Christensen, Ph.D., predicted that “through trait development, better genetics and improved crop management practices, we can continue to increase average yields for many years to come.” Even using the government’s conservative projections, switchgrass sequesters more carbon than any other raw material evaluated by EPA, which released its official analysis on advanced biofuels earlier this month, says Ceres.
目前的研究假设柳枝稷的产量低至每英亩 2 到 4 吨。桑迪亚国家实验室与人合着的一项备受推崇的生物燃料研究使用每英亩保守的 6 吨生物质作为能源草，类似于美国环境保护署的估计（美国环保署). The new Ceres results could cause policymakers to re-think energy crop production assumptions. Ceres chief executive Richard Hamilton says that Ceres needs additional data before formally proposing new benchmarks, but said the “writing was on the wall.” He added: “These results are not surprising when you look at the impact that utilizing modern biology has had on food crop yields, like corn, which has seen a five-fold increase since the first hybrids were introduced.”
EPA 提案遭到蔑视
报道称，对于柳枝稷来说可能是个好消息，但对玉米和其他以作物为基础的乙醇来源来说却是个坏消息，EPA 的生物燃料提案让两党的立法者都皱起了眉头 普氏. The agency’s plan to assess the “indirect effects” of biofuel production drew bipartisan condemnation from House representatives from farm states, who fear EPA’s standard could put an end to corn-based ethanol production. EPA’s proposed plan includes controversial measurements associated with land use, as the agency expressed desire for croplands to be used for food over fuel. Production and transportation of certain fuels, including ethanol and biodiesel — known as “significant indirect” emissions — also figure into the proposed plan.
“You are going to kill off the biofuels industry before it gets started,” Representative Collin Peterson, a Minnesota Democrat who chairs the full Agriculture Committee. Peterson vowed not to vote for any climate-change legislation unless corn-ethanol producers were protected. Representative Jerry Moran, a Kansas Republican, said he planned to introduce legislation that would prohibit EPA from using such an “indirect effect” standard until the science is better proven. “This industry is struggling to survive,” Moran said, adding that the indirect land use standard: “is one more nail” in the coffin of the industry.
Margo Oge, EPA director, said that under the proposed rule, 15 billion gallons of first generation corn-ethanol production was “grandfathered” in, and would not be trimmed back under the Renewable Fuels Standard. “We are very optimistic of the future of the second generation of biofuels,” she said, a telling referral to ethanol produced from cellulose and other farm waste, rather than corn-based ethanol. Critics say that corn-based ethanol actually creates more emissions than it removes from the environment.
西瓜可以使来源多样化
为生物燃料组合添加另一个可能的来源，美国农业部科学机构农业研究服务（ARS) studies have shown that simple sugars in watermelon juice can be made into ethanol. As opposed to growing the crop specifically for fuel, which could cause problems under the new EPA proposals, biofuel would be made from waste watermelon left after the food crop is harvested. In 2007, growers harvested four billion pounds of watermelon, while around 800 million pounds — 20% of the total — were left in fields to be plowed under because of external blemishes or deformities.
Chemist Wayne Fish’s ethanol studies at the ARS South Central Agricultural Research Laboratory in Lane, Oklahoma, US, showed ethanol can be fermented from the glucose, fructose, and sucrose in waste-stream juices — what’s left after nutraceuticals lycopene and citrulline are extracted. Making ethanol offers the potential benefits of helping to defray sewage treatment costs associated with nutraceutical extraction, says ARS, as well as providing watermelon growers with a new market for their crop.
On average, a 20-pound watermelon will yield about 1.4 pounds of sugar from the flesh and rind, from which about seven-tenths of a pound of ethanol can be derived. To extract all the possible sugars, Fish is seeking to degrade the rind with chemical and enzyme treatments. He’s also evaluating different combination of temperatures, yeasts, antifoaming agents, and pH levels to optimize the system.
Lane 的科学家们还在研究一年生黑麦草、高粱和其他可以与西瓜轮作的作物，以便为加工厂提供全年的营养保健品或乙醇供应。