可再生天然气在美国加州迅猛发展

据1月14日Energy Global 报道，南加州天然气公司（SoCalGas）和Calgren Dairy Fuels宣布，加州南部中央山谷四家新增的奶牛场已经开始将牛粪产生的甲烷输送到位于皮克斯利(Pixley)的Calgren工厂。在那里这些甲烷将被加工成高质量的可再生天然气(RNG)，并加注到SoCalGas天然气系统中。

目前，Calgren工厂从10个地区的奶牛场收集了超过66000头奶牛产生的甲烷。预计新增的奶牛场将使该设施可再生天然气产量增加近一倍，进一步减少温室气体排放(GHGs)，并取代更多的传统天然气。Calgren与Maas Energy Works合作开发了四个新的乳制品消化器，以及自2018年以来运行的前六个乳制品消化器。

可再生天然气可以迅速减少温室气体排放，因为RNG从空气中吸收的污染物比它作为一种能源被消耗时排放的要多。Calgren工厂生产的可再生天然气被用作重型车辆（如过境巴士和长途卡车）的负碳燃料。自2015年以来，RNG作为运输燃料的使用量增加了577%，减少了700多万吨的二氧化碳的排放。

加州80%以上的甲烷排放来自有机物，如污水处理厂、垃圾填埋场、食品、绿色废物和农场。2016年，加州法律要求利用垃圾填埋场和乳制品等工厂的有机物，减少40%的甲烷排放，并规定需要向消费者提供这些可再生能源。该法律将推动已经在快速增长的可再生天然气的供应量继续保持上涨势头。在美国，ICF最近发布的一项研究表明，到2040年将有4450万亿英热单位的RNG可供使用，约占美国目前住宅天然气消耗量的90%。

SoCalGas正致力于让可再生天然气能够为公司在南加州的2100万客户提供燃料。作为一项广泛、包容的综合计划的一部分，该公司承诺到2030年用可再生天然气替代20%的传统天然气供应。

王佳晶 摘译自 Energy Global

原文如下：

Dairy biogas operation expands in California

Calgren Dairy Fuels and Southern California Gas Co. (SoCalGas) have announced that four additional Central Valley dairies have started sending methane produced from cow manure to Calgren's biogas operation in Pixley, US, where it is processed into high-quality, renewable natural gas (RNG) and injected into SoCalGas' system.

The Calgren facility now collects methane from more than 66 000 cows at 10 area dairy farms. The additional dairies are projected to nearly double the amount of RNG produced at the facility, further reducing greenhouse gas emissions (GHGs) and displacing more traditional natural gas. Calgren has partnered with Maas Energy Works to develop these four new dairy digesters as well as the previous six dairy digesters that have been operating since 2018.

RNG can rapidly cut GHGs because it takes more climate pollution out of the air than it emits as an energy source. The RNG produced at Calgren's facility is used as a carbon-negative fuel for heavy-duty vehicles like transit buses and long-haul trucks. Since 2015, RNG use as a transportation fuel has increased by 577%, helping displace over seven million t of CO2 equivalent.

More than 80% of all methane emissions in California come from organic sources like wastewater treatment plants, landfills, food and green waste and farms. In California, a 2016 law requires a 40% reduction of methane emissions from waste sources such as landfills and dairies, with provisions to deliver that energy to customers. The law is expected to bolster the supply of RNG that is already growing rapidly. In the US, a recently released study by ICF estimates that 4450 trillion Btu of RNG will be available by 2040, about 90% of the nation's current residential natural gas consumption.

SoCalGas is working to make RNG available to fuel the homes of the company's 21 million customers across Southern California. As part of a broad, inclusive and integrated plan, the company has committed to replace 20% of its traditional natural gas supply with RNG by 2030.