A few links to illustrate how easy it would be in the future to start generating electricity on a small scale with no special or materials etc.
Just bear in mind that the first few links below are aimed at school kids, which does show how simple the technology 'can' be, but at the same time, just think how easy it would be to upscale the basic principles, in face it amazes me why for both the hydro and wind turbines, that peoples first choice isn't something simple like a bike wheel, which is a good size, ready balanced and freely spinning on decent bearing....
VERY SIMPLE wind turbine projects:
http://www1.eere.energy.gov/education/pd...urbine.pdf
http://www.re-energy.ca/docs/wind-turbine-cp.pdf
http://www.re-energy.ca/docs/wind-turbine-cp.pdf
Improvised Hydro generators:
http://www.greenoptimistic.com/2010/03/0...I4VyI1yaAg
http://www.instructables.com/id/Hydropow.../?ALLSTEPS
http://makingyourown.ludlowsurvivors.com/WWPG.html