Of course, all of that CO2 was soaked up from the atmosphere the year before; but, had we just left the barley where it was, it, too, would have soaked up quite a bit, lowering the reduction relative to coal to 20 tons. And, in a market system, almost all of the barley production simply moves to a previously unfarmed area.
但以柳树为燃料将释放22吨的二氧化碳。当然，所有释放的二氧化碳均为一年前从空气中吸收；但如果依然种植大麦也能吸收很大一部分，从而导致与燃煤相比的减排量降低到20吨。而在市场体制下，几乎所有的大麦生产仅仅被转移到之前未开垦的地区。清理未开垦地区现有的生物燃料平均每年多释放二氧化碳16吨（这还很可能是低估的数字）。