Tuesday, April 10, 2007

My Friend's Electric... Dreams

I thought worth publishing in full as it (if true), puts what I have been banging on about for a long while as regards some 'eco'-cures and the media's reporting of same:

Letters: Electric cars
Electric cars will work only as limited urban transport

Published: 10 April 2007
Sir: Johann Hari sometimes talks sense but, on electric cars, he is talking through the back of his neck (Big Oil's vendetta against the electric car - Comment, 5 April). Battery-driven electric cars are charged with electricity from the mains, the majority of which is generated by fossil-fuelled power stations.

Electric cars would simply transfer the atmospheric pollution from the cars to the power stations.

If all road vehicles were switched to battery-driven electric it would require at least a 40 per cent increase in electricity-generating capacity. At present, we are struggling to achieve even 5 per cent of our electricity from renewable sources. But let us imagine we have Johann's magic battery.

At what rate could we charge? The largest appliance on our domestic circuit is the cooker, which might use 6kW at its greatest rate of use. Let us assume we could charge our battery at this rate for nine hours. We would then have stored 54kWh of electricity.

A modern car has an engine capable of producing a power output of anything from 100kW to 350kW. Most of the time, it is using only a fraction of that output. To drive up the motorway at 70mph probably requires something of the order of 45kW, depending on the size and weight of the car. Our 54kWh would enable us to drive for just one hour and 12 minutes.

We would need the ability to charge at a higher rate than is feasible on a domestic supply before we could think of using battery cars for anything other than limited urban use, no matter how clever our battery is.

Stan Ovshinsky's battery that Johann said "could run for 300 miles at 70mph on a single charge" would clearly require charging at about 20kW if it was charged in nine hours.

The exhaust pipe is merely in another place. So while in some ways going electric may be seen to be better than nothing, not going at all is better still. Try making a fun op-ed piece on that!

Why do so many 'solutions' involve making more stuff and simply adding to the problem?


From Grist - - A more reasonable look at what is possible and desirable

This is truly inspirational.

I (and, I suspect, a few others - http://junkk.blogspot.com/2007/04/my-friends-electric-dreams.html ) have had certain concerns on the promotion of electric power as non-polluting.

When it is in this form, aside from the consequences of manufacture, it seems a rare beacon of solar-powered reality in transport. To get a craft charged up, aloft and to its destination with no power input other than the sun is awesome.

It seems viable battery capacity is the only restriction on realising his dream of a 2 or 4-seat version, which is where the practicalities of personal or indeed small-scale cargo (couriers?) transportation kick in.

Now all we need in the UK is the weather. Mind you, looking out the window, and with a certain sense of irony global-warming-wise, that may soon not be such a problem.

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