Electric cars

[Michael]

This is what has been bugging me.
Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour (lucky guys, aren't they?).
It makes 150KWh energy needed to recharge the cars.
Assume 10 hours (overnight) charge. It means 15kW of power (minimum)
is delivered to the house.
Do we have an infrastructure to support it?
Am I missing something?

 

[Jeroen Belleman]

[...]
Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour [...]
Do we have an infrastructure to support it?

On average, a car needs nowhere near 75kW. Some 10 to 15kW
should do fine. Even so, you are right to believe that the
current infrastructure wouldn't suffice if everyone used
electric cars.

Jeroen Belleman

 

[Bob Eld]

This is what has been bugging me.
Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour (lucky guys, aren't they?).
It makes 150KWh energy needed to recharge the cars.
Assume 10 hours (overnight) charge. It means 15kW of power (minimum)
is delivered to the house.
Do we have an infrastructure to support it?
Am I missing something?

Answer, NO. We do NOT have an infrastructure to support electric cars. Keep
in mind that an auto engine or motor, electric or gas uses a small fraction
of its available power most of the time. Therefore the problem is not as bad
as you propose.

Another issue is that 1/2 of the electricity generated in the US comes from
burning COAL. What is the point of eliminating convenient liquid fuels and
replacing them with the dirtiest fuel available and hooking up to that fuel
with expensive 400 mile long extension cords?

Electric cars make little sense until the electricity itself is green or
nuclear, non polluting.

 

[Michael]

[...]
Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour [...]
Do we have an infrastructure to support it?

On average, a car needs nowhere near 75kW. Some 10 to 15kW
should do fine. Even so, you are right to believe that the
current infrastructure wouldn't suffice if everyone used
electric cars.

Jeroen Belleman

.....a car needs nowhere near 75kW. Some 10 to 15kW....

You are probably right, but keep in mind that most of the people (at
least current driving generations) won't accept that. It will take
years and years and years (generations) to change this redneck my-
truck-must-be-bigger-than-your-truck attitude. (

 

[Spehro Pefhany]

[...]
Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour [...]
Do we have an infrastructure to support it?

On average, a car needs nowhere near 75kW. Some 10 to 15kW
should do fine. Even so, you are right to believe that the
current infrastructure wouldn't suffice if everyone used
electric cars.

Jeroen Belleman

There might be a hidden benefit to having large numbers of electric
cars. Nuclear plants run best @100% and storage of energy is a
potentially huge cost. Other generation methods have similar
limitations (eg. solar is only available when the sun is shining)
unless they involve burning of fossil fuels. Having millions of high-
capacity batteries paid for by consumers might not be such a bad
thing. Those willing to load- level the grid (including the option to
supply energy back into the grid) could get big discounts on the net
cost of the energy they use. Most cars sit in a parking lot 90% or
more of the time, so they'd be available for such duty.

 

[Eeyore]

This is what has been bugging me.
Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour (lucky guys, aren't they?).
It makes 150KWh energy needed to recharge the cars.
Assume 10 hours (overnight) charge. It means 15kW of power (minimum)
is delivered to the house.
Do we have an infrastructure to support it?
Am I missing something?

NO, you've found one of the fatal flaws although your numbers are a
little oversimplified.

NO-ONE NEEDS 200 hp to commute to work and before long the option's
unlikely to be available to them either through legislation, taxation or
the simple price/availability of fuel. Average WORLD car engines average
< 100 hp.

I suggest you also look at how long batteries last. Plus the miserable
efficiency of average electric power generation. 'New generation' diesels
@ 40% are going to look very attractive.

Electrolytically produced hydrogen is even more laughably inefficient.

Graham

 

[Eeyore]

[...]
Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour [...]
Do we have an infrastructure to support it?

On average, a car needs nowhere near 75kW. Some 10 to 15kW
should do fine.

That's as idiotic as 200hp ! 0 - 60 in one minute maybe ?

Graham

 

[Eeyore]

Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour [...]
Do we have an infrastructure to support it?

On average, a car needs nowhere near 75kW. Some 10 to 15kW
should do fine. Even so, you are right to believe that the
current infrastructure wouldn't suffice if everyone used
electric cars.

.....a car needs nowhere near 75kW. Some 10 to 15kW....

You are probably right, but keep in mind that most of the people (at
least current driving generations) won't accept that. It will take
years and years and years (generations) to change this redneck my-
truck-must-be-bigger-than-your-truck attitude. (

And thereby hangs the problem of the USA. Everything must be HUGE to impress
since you have no concept of asthetics or subtelty.

Not a problem for the rest of the world of course. We can get on fine without
you. Better in fact without all those US inspired resource and life sapping
wars you love so much.

Graham

 

[krw]

Michael wrote:

Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour [...]
Do we have an infrastructure to support it?

On average, a car needs nowhere near 75kW. Some 10 to 15kW
should do fine. Even so, you are right to believe that the
current infrastructure wouldn't suffice if everyone used
electric cars.

.....a car needs nowhere near 75kW. Some 10 to 15kW....

You are probably right, but keep in mind that most of the people (at
least current driving generations) won't accept that. It will take
years and years and years (generations) to change this redneck my-
truck-must-be-bigger-than-your-truck attitude. (

And thereby hangs the problem of the USA. Everything must be HUGE to impress
since you have no concept of asthetics or subtelty.

Have you looked in a mirror (either figuratively or literally)
lately?

Not a problem for the rest of the world of course. We can get on fine without
you. Better in fact without all those US inspired resource and life sapping
wars you love so much.

Not to worry, you Europeons will be at each other's throat again
soon.

 

[Charlie E.]

[...]
Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour [...]
Do we have an infrastructure to support it?

On average, a car needs nowhere near 75kW. Some 10 to 15kW
should do fine. Even so, you are right to believe that the
current infrastructure wouldn't suffice if everyone used
electric cars.

Jeroen Belleman

But, of course, not everyone will buy an electric car immediately when
they become available. As more and more cars come on line, then the
electric company will be doing some dancing to put in all the
additional service throughout all the towns and cities to support the
additional demand

Either that, or solar chargers of some sort will become extremely
popular...

Charlie

 

[nospam]

Those willing to load- level the grid (including the option to
supply energy back into the grid) could get big discounts on the net
cost of the energy they use. Most cars sit in a parking lot 90% or
more of the time, so they'd be available for such duty.

How much of your car battery capacity would you be willing to sacrifice to
load level the grid?

If you are prepared to sacrifice a significant amount what is the point
lugging a heavy half empty battery around the country with you? Why not
have a smaller battery to start with?

What does a daily (twice daily?) charge/discharge cycle do for the already
short life of lithium batteries?
--

 

[Eeyore]

Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour [...]
Do we have an infrastructure to support it?

On average, a car needs nowhere near 75kW. Some 10 to 15kW
should do fine. Even so, you are right to believe that the
current infrastructure wouldn't suffice if everyone used
electric cars.

But, of course, not everyone will buy an electric car immediately when
they become available. As more and more cars come on line, then the
electric company will be doing some dancing to put in all the
additional service throughout all the towns and cities to support the
additional demand

And the total efficiency of all this extra generated electricity from power
station fuel input to vehicle drive train is ??? Compared to say 40% for new
generation diesels for example ?

I can tell you it won't look very impressive, plus think of all the
batteries you'll have to replace.

Either that, or solar chargers of some sort will become extremely
popular...

Have you seen the price of solar cells ? Plus there's not much sun at night.
Fear not, mere politically incorrect inconveniences.

Graham

 

[Eeyore]

You missed the words "on average" .... Accelerating from 0 to 60 might
draw 75 kW -- for ten seconds.

mass = 2.5 tonne SUV. power in = 75kW

In 10 secs energy delivered = 750kJ

Energy = 1/2 mass.v^2

v^2 = 2 (Energy/mass) = 2(750kJ/2500) = 600

v = 24,5 ms-1 = 88 kph = 55 mph

So almost. But your motor and battery has to be rated for 75kW. Now try
uphill !

Once your AT sixty your demand drops precipitously.

About 20kW for US size vehicles.

Graham

 

[Eeyore]

Not to worry, you Europeons will be at each other's throat again
soon.

What on earth makes you think that ? How about another US Mexico war ?

Graham

 

[Eeyore]

How much of your car battery capacity would you be willing to sacrifice to
load level the grid?

If you are prepared to sacrifice a significant amount what is the point
lugging a heavy half empty battery around the country with you? Why not
have a smaller battery to start with?

What does a daily (twice daily?) charge/discharge cycle do for the already
short life of lithium batteries?

Depends on the depth of discharge.

Graham

 

[Ecnerwal]

* As just one example, in order to meet environmental regulations in the
US, Toyota Prius's sold here must restrict their battery use to something
like just 7% of their available battery capacity -- any more, and the
projected life of the battery pack falls below the magic 10 years
mandated by the EPA. Relax that rule, let the battery pack become a 2-
or 5-year maintenance item, and you could save a lot of gasoline right
here right now -- but the lefty fundamentalists wouldn't stand for it,
because someone, somewhere, might actually make a profit.

Well, they'd have to redesign the car to make the battery "pack" at all
economical to replace in the first place. It's not exactly a cordless
tool, swap the pack deal, and the "pack" alone costs more than most used
cars. Only one or two states require that it keep working for a
reasonable period of time - anywhere else, it dies, you have a humongous
repair bill, or a dead (yet pretty) car.

Thing being, a Honda Civic hatchback gets nearly the same milage, did so
years before the Prius came out, and isn't dead with no economically
sensible repair at 10 years (if you actually get 10 years).

The current crop of hybrids are a car maker's dream, as they will need
utterly nonsensical repair bills to ever become old cars, so they'll be
run off to the junkyard at an early age.

 

[James Arthur]

[...]
Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour [...]
Do we have an infrastructure to support it?

On average, a car needs nowhere near 75kW. Some 10 to 15kW
should do fine. Even so, you are right to believe that the
current infrastructure wouldn't suffice if everyone used
electric cars.

Jeroen Belleman

There might be a hidden benefit to having large numbers of electric
cars. Nuclear plants run best @100% and storage of energy is a
potentially huge cost. Other generation methods have similar
limitations (eg. solar is only available when the sun is shining)
unless they involve burning of fossil fuels. Having millions of high-
capacity batteries paid for by consumers might not be such a bad
thing. Those willing to load- level the grid (including the option to
supply energy back into the grid) could get big discounts on the net
cost of the energy they use. Most cars sit in a parking lot 90% or
more of the time, so they'd be available for such duty.

So the premise is Joe Average burns 13kWHr driving to work,
the grid taps him for another 15kWHr while at work, he burns
12kWHr driving home, then refills 40kWHr overnight.

But plug-in hybrids' premise/promise is to use most or all of
their charge on the way to work, recharge, then drive home.

GM's 'Volt' goes up to 40 miles on its 16kWHr pack before
cranking up its ICE. And that costs $40k.

So when he gets to work, Joe's battery is empty, thirsty for
juice.


As a first step to ultraefficiency, superlight, streamlined cars
make sense. Add serial hybrid drivetrains if you want to go the
extra mile.

(Amory Lovins says 2/3rds fuel savings is possible for
about $0.15/liter.)


Better to use less energy to start with than to figure out
better bleeding edge new ways to juggle and keep using
the same amount.

Cheers,
James Arthur

 

[Richard The Dreaded Libertarian]

There might be a hidden benefit to having large numbers of electric
cars. Nuclear plants run best @100% and storage of energy is a
potentially huge cost.

Yes, nuclear would solve a lot of problems, like CO2 and "dependence on
foreign oil".

The REAL problem is, how do we get this information through the thick
skulls of the paranoid bureaucrats?

Thanks,
Rich

 

[James Arthur]

Well, they'd have to redesign the car to make the battery "pack" at all
economical to replace in the first place. It's not exactly a cordless
tool, swap the pack deal, and the "pack" alone costs more than most used
cars. Only one or two states require that it keep working for a
reasonable period of time - anywhere else, it dies, you have a humongous
repair bill, or a dead (yet pretty) car.

Thing being, a Honda Civic hatchback gets nearly the same milage, did so
years before the Prius came out, and isn't dead with no economically
sensible repair at 10 years (if you actually get 10 years).

Parallel hybrids in conventional bodies don't really do
much better than my Acura--Mom's Civic Hybrid gets about
44mpg, I get about 41mpg. The hybrids /are/ more efficient,
but her car's heavier and more powerful. It needn't be
either.

The 2009 Nissan Altima Hybrid rates 35mpg and has a 158hp
2.5L gas engine.

Sheesh. That should be 40hp electric, plus a 20hp ICE for
recharging. Much more efficient, lighter, AND faster. A
lighter car doesn't need as big an engine to be fast. Easier
to make. Lighter=less materials used, cheaper, less waste, etc.


James Arthur

 

[James Arthur]

Michael wrote:
Imagine a family with two electric cars. 100HP (75kW) engine each -
not too big, is it? On an average workday each driver commutes for on
hour [...]
Do we have an infrastructure to support it?
On average, a car needs nowhere near 75kW. Some 10 to 15kW
should do fine. Even so, you are right to believe that the
current infrastructure wouldn't suffice if everyone used
electric cars.

But, of course, not everyone will buy an electric car immediately when
they become available. As more and more cars come on line, then the
electric company will be doing some dancing to put in all the
additional service throughout all the towns and cities to support the
additional demand

And the total efficiency of all this extra generated electricity from power
station fuel input to vehicle drive train is ??? Compared to say 40% for new
generation diesels for example ?

I can tell you it won't look very impressive, plus think of all the
batteries you'll have to replace.

Either that, or solar chargers of some sort will become extremely
popular...

Have you seen the price of solar cells ? Plus there's not much sun at night.
Fear not, mere politically incorrect inconveniences.

Graham

Put windmills on top of the cars & they'll recharge themselves on
their way to work. And painting them green will provide more green
jobs too, saving the planet and the economy. Win-win.

Cheers,
James Arthur