Wednesday, 13 April 2011
Perpetual motion at last?
The idea that electric cars are a panacea for conservation of energy and the environment is wishful thinking.
Any physicist will confirm that you cannot get something from nothing.
If electric cars are able to produce more, or even the same energy output unloaded that is put into them, then mankind would have at last achieved perpetual motion it seems to us.
These cars will need to be powered from either, oil, gas, coal or nuclear power stations. I think the Green movement must believe that renewables can achieve this sort of energy when it is becoming increasingly evident that it is pretty useless and needs massive subsidy to be pretty useless too.
Assuming then that we have not achieved perpetual motion, then we must accept that these cars, loaded, will lose much energy from friction and wind resistance and indeed the need to slow them more rapidly than to accelerate. Added to this is the effect of hill climbing where even more power is needed but is simply not returned, on descent, because energy is used to overcome gravity so that we are not too fast in descent; thus cannot use the energy consumed in the ascent.
So how does the cost of their manufacture, in terms of energy used, design and disposal, compare with current vehicles and how do they affect the environment when the energy source is considered?