Partial recharging is OK for town use, but if we want full electric for the
road too we do need full and fast recharging, which as Robin said is already
possible with current Lithium batteries but a bit long: 8mn is a hell of a
lot. 2 or 3mn as claimed by EEstor would be more like it.
A person driving a pure electric vehicle in the city who runs out of power
will be stranded.
Or maybe on the contrary unmanned slow recharging stations will be
ubiquitous because they require very little investment and real estate
compared to gas stations, and they will allow one to recharge enough to get
home or to the next "real" power station.
Michel
----- Original Message -----
From: "Jed Rothwell" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Wednesday, May 03, 2006 4:12 PM
Subject: Re: "Fully Charged in About 8 Minutes"
Robin van Spaandonk wrote:
>My argument holds in town too Robin. It's OK not to be able to
fast recharge
>an electric bicycle because you can switch to another source of power
>(your
>muscles)
Actually this can be challenging for older people, because electric
bicycles tend to be heavy. But many things about bicycles are challenging,
such as thunderstorms.
>We won't have "The Really Good Battery" as Chris calls it until we
have fast
>recharge plus other characteristics such as acceptable lifetime, cost,
>weight and volume for the required kWh value.
[snip]
But the new Lithium batteries *do* have fast recharge capability,
so a quick stopover at a roadside charging station shouldn't be a
problem. Such charging stations *do* need to have heavy duty power
supplies . . .
I think this would be a problem. Not because of technical limitations, but
because of commercial limitations. If people can recharge cars at home
conveniently at the same price (or less) than as a charging station,
people will seldom use charging stations. So there will be few stations. I
expect you would find only a few scattered around at shopping malls or
McDonald's. You will have to pay to use them, but the stores will install
them mainly as a way to attract customers. Swank office parks may have
them. Some swank malls and offices already do have charging stations, in
fact.
A person driving a pure electric vehicle in the city who runs out of power
will be stranded. There may be charging stations along major highways,
because all drivers will run out there.
These cars will need a good warning system for low power conditions. Maybe
it could incorporate a GPS and voice saying "you may not have enough power
to reach your destination [return home] [reach your office]."
I think readers here failed to understand the point I made yesterday about
partial recharging. It is a little difficult to imagine how this works
unless you have experience using electric vehicles. (I am one of the few
people in the U.S. who does.) A 5-minute partial recharge is almost as
good as a full charge for many purposes. As I said, if the low charge
warning is flashing and you need to go to the grocery store, a five-minute
recharge would be fine, whereas a one-hour recharge would be annoying.
Many urban trips are short. After you get back from the grocery store, you
can fully charge the car at your leisure.
We tend to think of refueling as an all or nothing process, because it is
a nuisance to go to the gas station, pay with a credit card and so on, but
there is no particular need to "fill 'er up" every time with an electric
vehicle. (I am assuming the power supply is conveniently located near
where you park the car.)
Furthermore, with the price of energy from a roadside station likely to be
at a premium, most people will likely opt for home charging over night,
and save.
The price would have to include a premium to cover rent, personnel and
equipment. This is why there will be few dedicated charging stations. On
the other hand, it would not cost McDonald's much to add one or two
chargers to their parking lot. Some people who driving a long distanced in
the city will go there only because they need power, and since it is
likely to take 15 or 20 minutes even with a fast recharge battery, they
are likely to stick around and eat something. McDonald's might limit the
amperage to stretch out the visit.
- Jed
