Saturday, September 22, 2007

92 Miles Square of land to Power the USA As many commenters  have noted,  92 miles square is  much different from 92 square miles.  The article is really speaking of 92 x 92 = 8464 square miles. Also noted is this is solar thermal.  Not photovoltaic.  Solar thermal is much more efficient at converting the heat from the sun to electric power but is much harder to put on your roof.  Solar thermal works at commercial power plant quantities. That being said, this is an opportunity to do some math.  We know the sun provides about 500 watts/square-meter.*  So we go to www.onlineconversions.com and convert 8464 square miles to 21,921,659,365 square meters.  Multiply by 700 to get about 11 Tera-Watts. The only thing left is to add up the amount of energy used in the USA and compare to 11 Tera-Watts.  Is it just the electric use or does it claim all the liquid fuel energy users as well?  How would we convert all the liquid fuel applications to electricity? * The referenced article actually claims 1000 watts/square meter at noon on a clear day.  I've divided by two to account for some clouds and rotation of the earth. 10:10:15 PM  permalink  comment []

© Copyright 2007 Joe Biegelsen. Last update: 9/27/2007; 9:24:24 PM.