dr-baker wrote:Well, that is only my perception of it, of course. I don't remember reading much to prove I'm right. But I do remember once reading that a lot more CO2 is used in both the manufacture and disposal of a Toyota Prius compared to a standard internal combustion car. I wonder if Faustus or Mario could confirm or refute my prejudices?
I do recall that there was a report that claimed that a Toyota Prius caused more environmental damage over its life cycle than a Hummer, but there were also several papers that tore the assumptions that were made in the original paper to shreds, since they relied on some very optimistic assumptions in some areas and some very pessimistic assumptions in others (particularly over how long those vehicles would be used for).
That said, whilst there might be a difference in the manufacturing and disposal stages, the energy expenditure during those stages is relatively low compared to the amount of fuel energy that you get through when driving your car. In the UK, for example, the Department for Transport reckons that the average person does about 8,500 miles a year; if the average person can get 35mpg a year, that equates to about 240 gallons, or around 1100 litres, of fuel per year. A litre of petrol, in turn, has about 35MJ of energy, so each year your average driver uses the equivalent of around 38,000MJ of energy (about 1.5 times as much energy that you average household uses per year for domestic purposes).
As to the question of whether or not it would be more efficient for that energy to be distributed through the national grid, it might well be the case - it is currently an issue of debate, but given that your average power station tends to work under constant load and power losses through the national grid are relatively low, there is some evidence to suggest that the net emissions from an electrically powered vehicle might still be less than the equivalent petrol engined car. I don't believe that a definite answer has been reached on that question, however, so that may change as time goes on.
. A series with an open slate has my interest, for science!
