70% loss is a great exaggeration,Typically, power losses are 1% per 100 miles of transmission line (at the 500,000 volt plus range, at lower voltages, the losses are greater). Ambient superconductors or equivalent materials are the best solution for this problem and I believe that within 10 to 15 years these will be reality. I cannot discuss that in public, though, so if you want to know more, you'll have to PM me (16 of my patents have to do with superconductivity).
Zeev