detroit is going to come back, but america s back in part because you are. reporter: but there are speed bumps. manufacturers this year are showcasing to rave reviews century old technology, piston engines and high horsepower. at the top of the carbon heat, the new corvette z-06 with 560 horsepower. the things people are buying are trucks and suvs, and that means people want size. they want comfort. they want power. reporter: last year ford sold 763,000 f-series pickups but only 35,000 hybrid c-max vehicles. two major battery-makers for hybrid and electric cars went bankrupt as did electric car-maker fister and an electric car-maker installer. one proponent of green energy wants to see more bankruptcies like this because it s a sign of a government pushing the boundaries of energy research and development. this is why i would love to see both liberals and