He thinks second-generation biomass could, in theory, generate 350 billion litres of biofuel per year - essentially equivalent to all of the US's oil imports.

他认为，理论上第二代的生物质量（biomass）可以每年产生3500亿加伦（13亿方）生物燃料——基本上等于全部美国石油进口。

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Niagara Falls, the collective term for the three waterfalls that dominate the border between New York state and Ontario, Canada, flows at a rate of up to two million litres per second.

BBC: Daredevil duo is the first to scale Niagara Falls