A combination of biomass, aquifers, burning vegetable oil -- a process that, quite interestingly, was developed in Eastern Germany, at the time of its dependence on the Soviet Bloc.
综合生物，地下蓄水层，燃烧植物油-- 这是一个东德设计的流程， 有趣的是 那个时候东德 还依靠着苏联。