It takes A LOT of energy to develop and implement green technologies. As environmental costs are always disregarded in economic calculations, the madness of shipping Prius batteries twice around the globe for their production-assembling-sales cycle never registers in the mind of environmental activists. The so called green technologies are, in fact, another artificial "bubble" to sustain the growth of the credit-based economy, which exactly IS based on growth for the sake of growth. There is a name for this: http://en.wikipedia.org/wiki/Greenwashing
Now for a bit of constructive input: solutions cannot be found from within the system that causes the problem in the first place, although the contradictions that arise in the process always contain the seeds of the gradual change that eventually will bring about a new system.
In this particular case, no amount of updating the basic concept of an ever-more-complex mechanical vehicle will ever get us anywhere close to the much fanfared "zero carbon impact". It is as an unattainable pipe dream as perfect elective democracy or the American Dream. Both are ideals taken out of their context and with their actual cost disregarded.
In this particular case of "green technologies", we are to ignore the energy necessary for extracting minerals to produce steel, glass and plastic, moving them around the globe and building facilities to produce, store and sell the products made of them. The impact of later releasing most of the energy, previously bound in carbon fuel, into the atmosphere as heat, is never calculated into the environmental impact of "green technologies" either. It is as if wind turbines and hybrid cars fall ready-made from the sky and, upon the completion of their usage cycle, are miraculously absorbed back into where they came from without a trace.