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A PHYSICIST WRITES . . .
(January 2011)
Last month, a man rang our door-bell: “Were you thinking of selling your two old cars?” Now Mrs S and I are quite attached to our L-reg Micra and R-reg Corolla. They have never let us down — though perhaps I ought to check through some previous columns before insisting on that — and neither of us want to think about having to get used to a new(er) car soon. So the polite No thank you that I gave to the man hid a rather frosty inner reaction to his question.
Here are a few more ‘wintry’ thoughts: I understand that sales of winter tyres have shot up recently, what with the weather and with more people realizing that they give you a better grip not just on snow and ice, but also in temperatures up to about 7°C. However, you would also need to buy a set of wheel-rims for them, change the wheels over twice a year, and find somewhere to store the set that’s not in use ... is it worth it? Not for us, but I guess they might suit higher-mileage drivers. A warning, though: it’s reported that some insurers are actually viewing winter tyres as a vehicle modification calling for a higher premium. However, the Association of British Insurers declares that this is wrong.
Christmas itself is getting more fraught. Last year I decided that one of our two strings of festive lights (both older than the cars) was beyond repair and had to go. I then bought two more sets, at bargain price. This winter I felt I ought to get in more spare bulbs: they were easy to track down for the remaining old set, but impossible for the new ones. Even when I found a website listing more than fifty different types and ratings of Christmas bulb, neither of the two that I wanted was included. The shops where I had bought the new sets were no help at all.
And do Christmas cards have much of a future? Fewer will be sent, surely, as postage rates rise (they all go up again on 4 April, by 12–14%, so stock up in advance on stamps marked 1st and 2nd class, as they will immediately appreciate in value!). I guess the trend will be towards e-cards: this last Christmas we ‘received’ four of them. One was an e-mail with a picture and greeting attached, looking much like the glossy card that had been posted to us in previous years. I felt under an obligation to print it out and put it up, almost.
The other three were e-mails with links to websites where we were invited to look at the ‘cards’ that had been set up for us. But two of the links didn’t work, and the one e-card that we were able to view, though pretty to watch, soon caused my computer to seize up. So the spirit of Christmas-yet-to-come looks rather un-user-friendly to me. And won’t hackers and virus-senders find it easy to infiltrate the e-card business (if they haven’t done so already)?
Let’s get back to motoring. Last July I posed a few questions about electric cars: is their range ever going rise much above 100 miles (between charges)? Won’t it be reduced when the interior and the driver needs warming? And what artificial noise will have to be generated so that you can hear these cars coming?
Both the last two issues of Advanced Driving had articles on electric cars, which I scoured for the answers: nothing. Instead, we were told (a) that they are easy to drive, except perhaps for the lack of an ‘engine note’ to listen to; (b) that you get more engine braking than you might expect (it’s used to recharge the batteries a bit); (c) that because of a desperate need to minimize energy consumption, the big contest between producers of electric cars will be over ways of reducing weight and air resistance; and (d) that we can therefore expect eye-catching designs (which may incorporate smaller windows, though, glass being heavier than metal panel).
But my own questions I’ve had to research elsewhere. Much work is going on to improve battery technology, of course, but no-one is promising spectacular increases in mileage per recharge yet. The highest range I have seen actually advertised is 245 miles, for the Tesla Roadster sports car — except that if you drive it like a sports car, you will be lucky to get half that figure!
That’s one problem with electric cars: their range depends greatly on how they are driven. Another is ‘range anxiety’: the fear that both owners and potential owners have of not reaching their destination. Also, the battery will deteriorate (increasing the anxiety, of course) and need to be replaced every few years — at a cost of several thousand dollars in the case of the Roadster.
If you want to be warmed while on the move, this will indeed draw energy from the battery and so reduce the range. But interestingly, a simple ‘resistance’ heater (like a fan heater in your home) turns out not to be the most efficient sort. Some electric and hybrid cars have a heat pump, working like a fridge but in the opposite direction: capturing heat outside and releasing it inside. In hot weather, the pumping is reversed, so that you are effectively inside the fridge. Air-conditioning can even be driven by solar power.
The hazard caused by electric vehicles as they silently approach pedestrians is taken seriously both by researchers, who have found that the danger is greater at low speeds (surprisingly?), and by manufacturers, who are introducing all sorts of noises under the bonnet.
There’s much more I could say about this and other aspects of electric cars, but it will have to wait for another column. Certainly, to get used to their distinctive characteristics some drivers will need to ‘re-educate’ themselves. In fact, I’m wondering if one day Mrs S and I might even school ourselves to think electric...
Peter Soul
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