[sci.energy] Tech details on GM Electric Car

mbutts@mentor.com (Mike Butts) (01/17/90)

Page 13 of the 1/15 issue of Automotive Electronics Journal (AEJ) yields the
following details on the GM Impact electric car prototype which was in the
general press lately.

Impact (what a great name for a car! :-) is a two-seat all-electric prototype
car.  2550 pound gross weight, 0-60 MPH in 8 seconds, top speed 75 MPH, 0.19
drag coefficient, cruising range 120 miles.  Batteries are a tray of 32 10-volt
lead-acid cells weighing 870 pounds. 25K mile life is given for the battery
set, which is sealed for life and does not need water.  Other text vaguely
refers to a one year battery lifetime.  Cost of ownership is said to be 2X
gasoline cars, but no other figures are given here.  An engineering manager
predicted doubling life within 2-3 years and admits that life needs to be
improved before marketing is feasable.  Lead-acid was chosen because it is well
known, but they stressed that production cars could have some other type of
battery.  A photo shows the battery tray, which is nearly as long as the car
and about one foot square being lowered from the aerodynamic body, which is on
a lift.

Aerovironment, Paul MacCready's company of human-powered aircraft fame, which
is 15% owned by GM, developed the MOSFET controller which generates AC for the
motors.  Delco Remy built the twin motors, one for each front wheel, which
together develop 114 HP and 94 ft-lbs of torque.  There is no transmission. 
Goodyear did the custom low-resistance tires.

The prototype was said to be ready for production but company officials
expressed mixed feelings about pursuing the project.  Company officials believe
a production EV could be built within 10 years.

Roger Smith is quoted saying "There is no sense in just transferring the
pollution problem from the cars to Southern California Edison."  The AEJ
article then takes issue with that point, citing statistics from Edison and LA
Power and Water to the effect that transportation accounts for more than 80% of
So. Cal's "air emissions", and the region's utilities account for only 0.5% of
that amount.  The utilities would become more efficient because of nighttime
electric car charging evening out load levels, says AEJ (ref. AEJ 12/18/89).

PS: I want one now.
-- 
Michael Butts, Research Engineer       KC7IT           503-626-1302
Mentor Graphics Corp., 8500 SW Creekside Place, Beaverton, OR 97005
!{sequent,tessi,apollo}!mntgfx!mbutts         mbutts@pdx.MENTOR.COM
Opinions are my own, not necessarily those of Mentor Graphics Corp.

phil@pepsi.amd.com (Phil Ngai) (01/18/90)

In article <1990Jan16.210512.287@mentor.com> mbutts@mentor.com (Mike Butts) writes:
|Roger Smith is quoted saying "There is no sense in just transferring the
|pollution problem from the cars to Southern California Edison."  The AEJ

Roger Smith is a f**king idiot.

--
Phil Ngai, phil@diablo.amd.com		{uunet,decwrl,ucbvax}!amdcad!phil
Peace through strength.

erc@khijol.UUCP (Edwin R. Carp) (01/18/90)

In article <1990Jan16.210512.287@mentor.com> mbutts@mentor.com (Mike Butts) writes:
>Page 13 of the 1/15 issue of Automotive Electronics Journal (AEJ) yields the
>following details on the GM Impact electric car prototype which was in the
>general press lately.
 
>Roger Smith is quoted saying "There is no sense in just transferring the
>pollution problem from the cars to Southern California Edison."  The AEJ

 Roger is not known for his brillance - look at what he did to Ross.  Roger -
what a jerk!

>PS: I want one now.

Put me on the list, too!  Screw how much it costs to own.  It'd be better than
driving a gas-sucker.  Besides, if you got stuck out in the middle of nowhere,
just whip out your solar-cell array and charge up your batteries!

That gives me a thought -- drive your car to work, then unfold your solar array
and let the sun charge your batteries while you work!
-- 
Ed Carp                 N7EKG/5 (28.3-28.5)     uunet!cs.utexas.edu!khijol!erc
Austin, Texas           (512) 832-5884          "Good tea.  Nice house." - Worf
"The best diplomat I know of is a fully activated phaser bank."  -- Scotty

harmons@osiris.WV.TEK.COM (01/19/90)

> Roger is not known for his brillance - look at what he did to Ross.  Roger -
>what a jerk!

Roger points out that they bought out Ross at $33 a share and the shares are now
worth $50 (WAW-December)

>driving a gas-sucker.  Besides, if you got stuck out in the middle of nowhere,
>just whip out your solar-cell array and charge up your batteries!

Oregon has a lot of "middle of nowhere" which doesn't get much solar radiation
between sunset and sunrise.

jans@tekgvs.LABS.TEK.COM (Jan Steinman) (01/19/90)

<That gives me a thought -- drive your car to work, then unfold your solar 
array and let the sun charge your batteries while you work!>

We're talking MAJOR unfolding here!  Assuming a 20HP engine running for 15 
minutes, 80% engine and charging efficiency, and 15% solar conversion 
efficiency, and nine-hour charge time (and even more improbably, you're parked 
on the equator, and it is noon all day :-), it would take 4.3 square meters of 
PV material.  (This also assumes that you do not use your brakes!)

Although I'm a solar advocate, I don't envision this happening anytime soon.  
Note that if the solar/electrical efficiency were closer to the 
electrical/chemical or electrical/mechanical efficiencies, it might be 
possible.  (Maybe if DOE would shift public subsidies to PV from that "other" 
technology?)

							   Jan Steinman - N7JDB
					Tektronix Electronic Systems Laboratory
					Box 500, MS 50-370, Beaverton, OR 97077
						(w)503/627-5881 (h)503/657-7703

fcr@saturn.wustl.edu (Frank C. Robey X5569) (01/19/90)

In article <1060@khijol.UUCP> erc@khijol.UUCP (Edwin R. Carp) writes:
>
>That gives me a thought -- drive your car to work, then unfold your solar array
>and let the sun charge your batteries while you work!

This sounds like a great idea, but when you calculate the amount
of solar radiation which is incident (say 1 kW per square meter)
and then multiply by the efficiency of the solar cells (say 12%) 
and the number of square meters (say 3) then you don't end up 
with a very big number (360 W).   When you consider the size
of the electric motors in these things you will quickly use 
up the energy you have accumulated over the 8 hours time.  Of
course if you don't have far to drive, then that is a different
story.

I have seen electric vehicles with the solar panels on the roof 
at Powercon, and even the salesmen admitted that they were a gimmick,
"meant for the future when we have 25%+ efficient solar panels".

Frank Robey
fcr@saturn.wustl.edu

mdbomber@portia.Stanford.EDU (Matt Bartley) (01/19/90)

In article <1060@khijol.UUCP> erc@khijol.UUCP (Edwin R. Carp) writes:
>> [... GM e-car]
>>PS: I want one now.
>
>Put me on the list, too!  Screw how much it costs to own.  It'd be better than
>driving a gas-sucker.  Besides, if you got stuck out in the middle of nowhere,
>just whip out your solar-cell array and charge up your batteries!
>
>That gives me a thought -- drive your car to work, then unfold your solar
>array and let the sun charge your batteries while you work!

	You're gonna need a really big solar panel to do this.  You couldn't
make a serious dent in the battery charge with a panel you could bring in
the car, unless it was a special (and fragile) folding panel.  With that,
you'd need it to take up the area of several parking spaces, so that probably
wouldn't work.
	It could be allright for emergencies, but it won't get you far.
Probably to the nearest place to plug an extention cord in. :-)
	You could use a large solar panel to power the car by having it based
at home, connected to charge batteries in the daytime, which you could then
transfer to your car batteries when convenient.  In fact, at the Stanford
Solar Car Project we have a car and solar rig that can do just this.

-- 
Internet: mdbomber@portia.stanford.edu                   Matt Bartley
Bitnet: mdbomber%portia@stanford.bitnet
	Riker: "You enjoyed that."                 -"Ensigns of Command"
	Picard: "You're DAMNED right!"                    Star Trek: TNG

john@anasaz.UUCP (John Moore) (01/19/90)

In article <1060@khijol.UUCP> erc@khijol.UUCP (Edwin R. Carp) writes:
>In article <1990Jan16.210512.287@mentor.com> mbutts@mentor.com (Mike Butts) writes:
]driving a gas-sucker.  Besides, if you got stuck out in the middle of nowhere,
]just whip out your solar-cell array and charge up your batteries!

For about 10 years... then you'll have enough charge to drive a few miles.
]
]That gives me a thought -- drive your car to work, then unfold your solar array
]and let the sun charge your batteries while you work!

You must work some awfully long hours!


-- 
John Moore (NJ7E)           mcdphx!anasaz!john asuvax!anasaz!john
(602) 951-9326 (day or eve) long palladium, short petroleum
7525 Clearwater Pkwy, Scottsdale, AZ 85253
Freedom and Communism are incompatable.

abbott@ms.uky.edu (Joel Abbott) (01/20/90)

>I have seen electric vehicles with the solar panels on the roof 
>at Powercon, and even the salesmen admitted that they were a gimmick,
>"meant for the future when we have 25%+ efficient solar panels".

One use for those solar panels that can be implimented today is
a little fan connected to the solar panel for sunny summer days.
What I would give to have some of that hot air expelled before
I open the door.  And those vinyl seats! ouch!

There are some aftermarket fans I have seen advertised that
fit into your rolled up window.  Nice!
-- 
Joel Abbott -> abbott@ms.uky.edu, abbott@ukma.bitnet, uunet!ukma!abbott
Blah blah blah.

cik@l.cc.purdue.edu (Herman Rubin) (01/22/90)

In article <1060@khijol.UUCP>, erc@khijol.UUCP (Edwin R. Carp) writes:
  
> That gives me a thought -- drive your car to work, then unfold your solar array
> and let the sun charge your batteries while you work!

This assumes that 

	The sun is shining

	You are parked in an open lot, not a lower floor of a ramp

	You get there in time to use a large area for your solar array;
	say several parking spaces worth.
-- 
Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907
Phone: (317)494-6054
hrubin@l.cc.purdue.edu (Internet, bitnet, UUCP)