Comments DaveBrook has made

  • 75 mph most efficient speed NOT

    You talk about 55 mph being an "optimal compromise" (presumably between fuel efficiency and time to get to one's destination) but at the end of the sentence refer to efficiency.  55 mph was a political compromise not some sort of engineering number.  Even though the aerodynamic slipperiness of cars has gotten much better since the behemoths of the 70s, they haven't gotten THAT much better.  I think you'll find that if you take a Honda Insight out on the highway, the most efficient speed will still be between 45-50 mph  (but haven't done it).  

    Are there any Insight (or other low "coefficient of drag" car owners out there want to tell us what their optimum speed is?  Thanks.On Umbra on speed limits posted 4 years, 2 months ago 10 Responses

  • Biofuels and agriculture

    In his new book Winning the Oil End Game, Amory Lovins describes a technically-feasbile way for ending the need to import oil in 20 years.  In the book he shows how 20% of our current imports could be offset with biofuels.  He, too, was concerned about the possible competition between (bio)fuel vs. food production and describes a scenario in which all the biofuels are created by lignin/cellulose production, not farm crops.  You can download the entire 300 page book and footnotes at www.oilendgame.com.On Umbra on hybrids vs. veggie-oil cars posted 4 years, 8 months ago 11 Responses