Nonsense spouted on NPR's "Science Friday"? - June 30

I'm the gent who posted "Questions on electrical distribution system and motor efficiency" last weekend. Thanks for the responses.
The reason I posed my questions was to be able to better contest assertions made by a guest on N.P.R.'s "Science Friday" on June 30. The host was interviewing someone who's put together a movie, now showing in a few cities, which supposedly documents how politicians, acting on behest of the oil and automotive industries, quashed efforts to develop electric cars in the mid and late 1990s. That is, these cars had batteries charged by household power, and a battery-powered motor.
The guest said these cars were sought in California, for their supposed advantage of eliminating tailpipe exhaust (for cleaner air). Some advantages he cited are ones I concede, such as the car can be lighter, as a heavy engine and transmission are not required. He said G.M. made these cars for a while and leased them, and they were quite popular, but ultimately, G.M. stopped leasing them, and destroyed them.
My reaction was that he was a non-technical person who didn't understand what he was asserting, and had overstated the case for electric cars, also convincing a lot of others who also aren't energy-savvy. He didn't seem to be aware of the drawbacks of using electrically driven cars; nor did he mention any.
Someone who knew about these electric cars called in, said they had very limited range for driving - about 30 miles - between recharging, and that was the main reason they fell out of favor.
I tried to reach Science Friday to challenge the guest, but the line was busy.
Anyway, my reasons for skepticism about the guest's arguements include the following:
-- Use of electric cars shifts the source of air pollution and CO2 to the atmosphere from tailpipe exhaust to power plant exhaust (assuming a fossil fuel is used for power generation, a safe assumption in the U.S.) Coal and fuel oil produce lots of pollution and CO2.
-- A widespread switch from gasoline to electric powered cars would require a huge investment in more generation capacity by electric utilities.
-- Although cars are known to have poor thermal efficiency (to my knowledge about 20% of the useful energy in gasoline is converted to mechanical power), similar inefficiencies abound in use of electric cars. Here is a list of inefficiencies that apply, and I'm sure others in this group could expand the list, or expound upon it:
- Fossil fuel plants have limited thermal efficiencies. I used to work at a power company, and about 1990 its best coal-fired plant had a thermal efficiency of about 35% (thermal efficiency compares the thermal equivalent of kilowatt-hours to the energy content of the fuel burned); - Impedance of power lines, and related factors result in energy lost in electric power distribution; - There are losses in each stage of each transformer to the homeowner's 120/240 VAC 3-wire connection to utility lines; - The converter used to charge a car battery will have losses; it has to be stepped down in voltage and rectified. - In the car itself, not all of the energy the battery applies to the motor will result in mechanical power (hence my previous question about the efficiency of DC motors.)
I'm very interested in responses from other posters. I intend to contact "Science Friday" about this. I suspect this guy was spouting a lot of nonsense.
M.H.
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M. Hamill wrote:

You may be a a non-technical person who doesn't understand what you are asserting.

They are avoiding you.

Large, fixed energy conversion devices are more efficient and cleaner operating than mobile systems.

Could be. It would be a great idea particularly if these systems were non-polluting.

However, they are much more efficient than automobile diesel and Otto cycle engines.

Trivial in multiple KV power transmission systems.

Do you obtain your power from a utility or, as would seem likely from your post, generate your own electricity?

The battery system can be designed so that rectified AC is usable at 117v. Losses in rectification are effectively zero.

??
No. The individual on Science Friday was not spouting a lot of nonsense. Others, however, . . . .
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Not quite. I'm a licensed P.E., although my background is Mechanical, not Electrical Engineering. I sought to learn about the inefficiencies (or lack thereof) associated with electricity distribution, and E/M energy conversion in DC motors.

Who can say how many other callers there were.

Agreed.
And right now, that's a huge if. Quickly reviewing existing options for large-scale power generation: 1. Coal: Worst fossil fuel source in terms of generating CO2 (although there are plans for a test plant to store CO2 from coal-fired power plant exhaust below ground.) Bulky, dirty, voluminous waste. If scrubbers are needed to remove SO2, reduces plant efficiency by about 15%. 2. Oil. Expensive. Fuel oil is dirty stuff, too. 3. Natural gas: expensive, though easy to burn, doesn't leave a lot of waste like coal. 4. Nuclear power: Expensive to build and so financially risky for investors that the only way to get investors interested currently is with gov't loan guarantees. Also, plutonium waste generated is very hazardous and has a half-life of 24K years. 5. Solar power: currently, expensive capital cost compared to alternatives. Also, sunshine is not reliable in most areas. 6. Hydroelectric power: virtually all tapped out. 7. Wind power: it's a stretch to say wind power can generate power on a very large scale. We all wish it could.
Hopefully, technological innovations will be developed that will allow economical power extraction from ocean waves, or other natural, renewable sources. That would be great.

I'll take your word on that.

Well, just because someone makes assertions about the efficiency and effectiveness of electric cars doesn't mean that such claims shouldn't be checked. And as I understand it, present limitations on battery technology severely limit how much energy can be stored in a car's battery, although some are working hard to develop batteries with much higher storage capacities.
For now, knowing some simple laws of physics will enable interested drivers to extract as many miles per gallon of gas as is physically possible. Where I live, in the Midwest, we have a large % of drivers who don't seem to care in the least about the cost of gas or the CO2 their large vehicles exhaust.
M.H.
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In my opinion, everything else in this thread but for your last paragraph is irrelevant fluff. The last paragraph is everything.
The average American puts every idea, policy, program, etc. through a rigorous, two-prong test:
1 Does it feel good? B Does it feel good now?
If the answers to those two questions are yes, nothing else matters. Even if the planet were to vaporize tomorrow, I am not sure it would matter.
So, I guess it might be a good to have a law banning vehicles that get over 10 miles per gallon. Let's get it overwith. Let's (quickly) put the atmosphere in such a condition that no one can deny that either there is global warming that should have been stopped or that there is no global warming and humans can burn everything on the planet that will burn.
I suspicion that to take the planet carbon neutral would require policies that would create the greatest economic depression yet seen.
But, take heart. Hurricane season is coming.
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ecarecar wrote:

Fossil fuels said to damage ocean life
By RANDOLPH E. SCHMID, AP Science Writer / 15 minutes ago/
WASHINGTON - Corals and other marine creatures are threatened by chemical changes in the ocean caused by the carbon dioxide from burning fossil fuels, a panel of scientists warned Wednesday.
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M. Hamill wrote:

in areas where it gets cold in the winter heat is needed to comfort the occupants and clear the windshields. doing this from batteries seems problematic. maybe with fuel cells the electricity could provide motive force and the hydrogen the heat.... (or maybe the other way round)
what kind of brakes do roadworthy electric vehicles have? what happens when the batteries go dead?
when you run out of "juice" on the road, how do you get recharged?
ask any golf course owner or manager about range, use, and maintenance of electric powered vehicles.
the problem with secret conspiracy theories is that it is well known that 2 or more people cannot keep a secret.
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TimPerry wrote:

Ha!!! That's easy. Back around 1990 I "manufactured" an electric car with a power-train of my own design. In the early "shake-down" days I ran out of electricity several times.
What you do is you get your pampered rear-end out and push. There is NO better cardiovascular workout than pushing a grossly overweight damn car several miles.

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ah, i see. the carbon based life form backup propulsion system.

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GM's supposed reason was they were not selling all that well. One thread a while back listed a few people's direct experiences with the EV-1. It was offered by rental car companies in the LA area. One experience went something like, 1) Picked up car at airport, drove downtown, nice 2) downtown hotel and 'charging' stations broke/outofservice. 3)contacted rental company about getting recharged, 4)they towed it and left a gasoline powered car.
EV's can be useful as in delivery fleets, much like propane-powered cars. But so far, the recharge time limits their usefulness to a radius < 1/2 their range.
<snip>

True, but their efficiencies are better. They also can have the extra equipment to remove/prevent some of the other 'nasties' like NOx and CO. So there *could* be a slight improvement over the thousands of cars idling in traffic.

That would depend on the time of charging. If delayed until the wee hours of the morning, it would mean that some regulating/peaking units just run longer into the night. Not more generation capacity, but more expensive fuel costs.

Yes, but EV opens up the possibility to use a much wider range of 'fuels' besides just petroleum.

Well, power lines have 'impedance' and 'resistance'. The impedance is much larger and causes problems with voltage stability and the maximum amount of power than can be transferred. But it isn't an energy loss. The resistance represents the energy losses and is usually pretty small, on the order of less than 5% of the total power flowing.

Substation sized transformers run >97% efficient. Even 'pole-pigs' can run >93%

Very true. But in some types of driving, the use of regenerative braking can save a substantial amount. And EV's lend themselves very well to such a setup (just modify the control algorithms). But only in certain driving situations (stop/go urban driving)

There is a lot of 'conspiracy theorists' about the disappointing life of GM's EV-1. But if GM (or any other car manufacturer) could make a car that was attractive to the public and cost only a fraction to operate of a gas car, I don't think GM would shelve it for their 'big oil buddies'. Rather, they would be producing (and selling) them as fast as they could. But the EV-1 was *not* attractive to the public. The 'public' voted with their pocketbooks. Gas was still cheap, the EV-1 was limited range, hours to re-charge, cost more, and was less versatile than an SUV. So the SUV's won, GM couldn't sell the EV, and pulled it from the market.
Some say it was pulled because of liability issues if the battery was damaged in a crash. But I think the simple truth is, people didn't like having to worry about where to plug it in all the time (i.e. lack of supporting infrastructure). It's not like you can pull into a parking garage and plug it in while at work/shopping. And as someone else mentioned, I don't know how well it would work in 'snow country'.
Who wants a second car that can only go about 30 miles away from home and back? Or can only be used in the summer? Definitely some downside.
With rising gas prices, and more 'public awareness', an electric vehicle *might* make a comeback. But GM's experience with the EV-1 probably left a 'bad taste' in their corporate R&D mouth, so things would have to change more than they already have before they'll try that again.
daestrom
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and
assertions
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supposed
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G.M.
If we could store 10 kWh in something the size, weight, and cost of a conventional car battery (instead of about 0.5 kWh), internal combusion engines would be relegated to aircraft and niche applications. It's the batteries, darn it...they just aren't good enough and they will never match an IC engine for kWh/kg.
Bill
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