Comments on: Hard Math https://blog.speculist.com/energy/hard-math.html Live to see it. Thu, 16 Dec 2021 08:21:00 +0000 hourly 1 http://wordpress.org/?v=3.6.1 By: Engineer-Poet https://blog.speculist.com/energy/hard-math.html#comment-794 Engineer-Poet Mon, 10 Oct 2005 08:08:36 +0000 http://localhost/specblog/?p=424#comment-794 A bushel of corn can be burned to make about 390,000 BTU of heat; the ethanol from that same bushel yields about 224,000 BTU, and there’s about 88,000 BTU of heat required for distillation.  A lot of that distillation is done with the very same natural gas and LPG which are expensive and in tight supply this winter, so fuel ethanol is literally competing with people trying to keep themselves warm.

Ironically, we could get more miles out of a bushel of corn by burning it, using the heat to run a generator, and charging batteries to run cars.  I did some numbers here.

]]> By: djnowhere https://blog.speculist.com/energy/hard-math.html#comment-793 djnowhere Sun, 09 Oct 2005 11:12:23 +0000 http://localhost/specblog/?p=424#comment-793 It was true in the 70s that ethanol production used more energy then the ethanol produced, but now you get about 1.6 units for every 1 you put in. For biodiesel its over 3 units out for every 1 unit in and there are new production techniques that have come about in just the last couple of years that make it way more efficient. You can make biodiesel from plants that grow on unfarmable land or from algea and they can make ethanol now from the whole corn plant. Check out http://biodieselnow.com

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