Here is Mike Snead’s Presentation from the Space Solar Power Track at the ISDC. It is a great analysis of future energy needs and availability.
Energy, SSP, and Jumpstarting America’s Spacefaring Future (52 charts; 13 Meg; PowerPoint 2003 format) This is the presentation given at the National Space Society International Space Development Conference 2009 in Orlando, FL. Speaker notes are included. (Copyright (c) 2009 Spacefaring Institute LLC. See title page notes for permitted uses.)
For more information about Mike Snead’s ideas see Spacefaring Institute LLC.