Re: four elements for EV acceptance - or one alternative

[Lee Hart <leeahart@earthlink.net>]

Michael A Perry wrote:
> We assume EVs are less expensive at MPG ratings than ICEs.

This is a good assumption if you are comparing equivalent vehicles being
driven the same way. EV conversions of ICE vehicles generally get better
"gas" mileage. The same holds true when you compare electric vs.
fossil-fuelled fork lifts, golf carts, and other vehicles.

> If we look at the inefficientcy of charging batteries
> (35% efficientcy for wet cells, I understand)...

Lead-acid battery charging efficiency routinely exceeds 80%, and can
exceed 90% with careful charging. Most of the energy loss goes into
deliberate overcharging because the charger is too "dumb" to shut off
when the batteries reach full charge.

Nicad and NiMH batteries have somewhat lower charging efficiency, and
self-discharge faster which is another type of loss. Nickel-iron are
worse yet. I don't know how lithium-based batteries fare on charge
efficiency.

> then charging costs may be very close
> to the cost of gas, at today's artificially low prices.

Electricity is "manufactured", so it will never be the cheapest form of
energy. But electricity can be generated from whatever the cheapest
source of energy happens to be at the moment, so the "true" cost of
electric energy will tend to always be among the cheapest.

Of course, prices can be rigged by taxes, monopolies, politics, etc. to
be anything.

> I'm not sure if maintenance costs are really so much less than an ICE.

Here again, we have 100+ years of comparative costs between EVs and ICEs
to draw upon. Whenever one owner pays all the costs (initial vehicle
cost, plus fuel cost, plus maintenance and repair costs over vehicle
life), EVs win. You generally find this situation for industrial
vehicles, fleets, buses, trains, etc. EVs cost more initially, but are
cheaper to operate and need less repairs, and so are cheaper over life.

> consider... the standard ICE can run for 125K miles w/o problems...

But also consider... 125k miles at an average speed of, say, 42 mph is
only 3000 hours: Your car is completely shot after 3000 hours of use.
There are endless examples of electric motors and their drive systems
that are far more robust.

Your refrigerator, air conditioner, and furnace are built for 30,000
hours of use; their electric motors will run 8 hours a day every day for
10 years, often with essentially zero maintenance. A fork lift EV will
run 8 hours a day for 10-20 years. There are electric trains, trucks,
and buses, with literally millions of miles on their electric motors
with negligible maintenance and repairs.

> I would assume, if you intended to drive your car forever, the cost
> of batteries and components would weigh in very close to the cost
> of overhauling an ICE...

Rebuilding an ICE is complicated, dirty, labor-intensive work; due to
the cost, most cars will never get another engine. But replacing
batteries is a normal, expected maintenance item; like tires, brakes,
exhaust systems, lights, etc. So replacing batteries is a cheaper,
quicker, more straightforward job (assuming the designers haven't gone
out of their way to make it difficult).

My own opinion is that exotic high-tech batteries are not yet
appropriate for EVs. Economics dictate a battery with a low
cost-per-mile. For now, that means lead-acid. Existing lead-acid
batteries have life expectancies in the 1-5 year range, and amortized
cost is around 5-10 cents per mile. That already compares very favorably
with ICEs.
-- 
Lee A. Hart                     Ring the bells that you can ring
4209 France Ave. N.             Forget the perfect offering
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phone (612) 533-3226            That's how the light gets in
leeahart@earthlink.net                  Leonard Cohen