That you seem to take a very parochial view of the world. That's okay; it's only human nature. That's why we have governments to inject externalities into individual economic decisions. And some of the most important externalities involve pollution, both "traditional" (e.g., smoke, CO, NOx, etc) and those that cause global climate change.
I'm pretty sure that a gas turbine hybrid car is about as efficient as an EV powered by a centralized gas turbine with distributed power, without the range limitations, but oil-based industrial power generation is very rare, as are small gas turbines, so it's hard to know for sure.
I don't think an automotive-size gas turbine could come anywhere near the efficiency of a large combined-cycle power plant. I know, for example, that the 500kW gas-fired turbines we have at work produce electricity with only 18% efficiency. The waste heat is used to drive absorption
chillers for cooling, which is their primary function. Electricity is just a byproduct. It still works out because the chillers do not require high-temperature heat; they work fine on the cooler exhaust from the turbines.
So if a 500kW stationary turbine only gets 18%, then I don't see how an auto-sized turbine could possibly do better.
The heat of vaporization of water is ~540 c/g, so in changing water from 30 C to steam at 1110 C, one third of the power used is the phase change (and half at a stem temperature of 570 C which is probably closer to large plants). But I don't know if power plants even try to reclaim that heat - it's normal for chemical engineering, but the point of a condensing tower is to lose the heat of vaporization to the environment, and powerplants around here all seem to have condensing towers.
I'm still trying to figure out if this really matters. In the coal plants I've read about, the spent steam is condensed at low pressure (60 mb) and 35C or so, so that the latent heat of condensation is released at the lowest possible temperature. Also, there is
usually a reheat cycle in which the steam from the first set of turbines is reheated in the boiler and then fed to a second set, presumably at a lower temperature. According to the Wikipedia article on coal power plants, the efficiency of a supercritical steam (540C)
turbine plant is about 40-45%, while I compute a Carnot efficiency of 62% for those temperatures. The difference is roughly the
same as the 1/3 loss you mention, but it would have to cover all other losses as well.
Coal plants typically have less than 40% efficiency because of this, though a "super critical" plant that avoids the loss from the heat of vaporization can approach 50%.
That just strengthens the case for the EV; I'd been assuming a conversion efficiency of only 35%.
In any case, we do know that a really good combined cycle turbine is about 60% efficient, but using the waste heat for another process can be up to 85% efficient, co-generation of hydrogen has an extra 25% efficiency (or 40% of the generated power) to work with. In real-world utility power plants the waste heat is clsoer to 100% of the generated power, which makes co-generation of hydrogen *more* than 100% efficient (compared to just the electric output, of course), which is a neat trick.
I still don't understand how this can be true. Cracking water into hydrogen requires much higher temperatures than the
temperatures at which spent turbine steam is condensed to water (35C). Increasing the condensation temperature would necessarily
reduce the efficiency of the turbine. And even if it were true, you'd still be better off burning that hydrogen in another large combined-cycle turbine and making more electricity
than sending it through a distribution network to automotive fuel cells that are only 50% efficient.
My point is: the average family can't really use an EV as their only car (though perhaps a student could).
Who says it has to be their only car? Many families have more than one car, and at least one could easily be electric.
I can't find good numbers on the percentage of all the oil used for transportation which is consumed by light-duty vehicles, but it seems to be about half, if the numbers I can find aren't just made up. So
That is, is there any advantage in efficiency, as opposed to choice of fuels. I don't think there's much - I think instead people are comparing extremely streamlined EVs to SUVs, which they would not replace. If you burn gas to make the electrical power, what's the MPG you'd get from a *comparable* EV?
You're exactly right -- that is indeed the proper comparison. And in this case, the power plant + EV still comes out well ahead because of the
much greater thermal efficiency of the central power plant. See this quote by Martin Eberhard of Tesla Motors in the recent Wired article:
"If you took the energy in a gallon of gas and used it to spin a turbine, you'd get enough electricity to drive an electric car 110 miles"
I don't know what numbers he used to get this exact figure, but it seems about right given what I know about the relative efficiencies
of the engines. Especially if the power plant is a combined-cycle gas turbine.
And of course you can make electricity from fuels other than gasoline, which is one of the EV's biggest advantages.
Any "surplus" heat that could be economically used to generate power is so being used, pretty much by definition, unless you're merely saying that a newly built power plant would be more efficient than an old one. There are a few places that use this waste heat for heating nearby buildings, which is wonderfully efficient, and reasonably common for private industrial power generation.
Right again. Cogen heat is also often used for cooling. My company does exactly that at our main campus.
We have three 500kW natural gas turbines
that produce electricity to offset (but not replace) our grid draw, and the exhaust heat drives the absorption chillers that
cool the buildings.
Much of the lost thermal efficiency of power generation is the heat used to convert water to steam.
Is this really true? I thought the limiting factor is the temperature of the steam from the boiler. The hotter, the better. Problem is, this is limited by the materials in the boiler (or reactor and steam generator, in the case of a nuke). Also, many large steam turbines use reheat cycles,
where the steam coming out of a turbine is passed back to the boiler and used to drive another turbine. Eventually the steam condenses,
but as long as this is done close to ambient temperature, the thermodynamic losses are minimized. Can you point me to an analysis?
Performing steam hydrolysis on the "waste" steam from the generating plant allows for remarkably good efficiency,
No matter what you do, producing hydrogen from water takes energy that has to come from somewhere. Any energy you use to crack water could alternatively be used to generate more electricity, i.e., to increase the plant's efficiency. Also don't forget that automotive fuel cells, while better than internal combustion engines, are still only about 50% efficient. Even if the hydrogen were a free byproduct, which it cannot be, you'd be better off burning it locally in a combined-cycle turbine and making electricity at 60% efficiency. Then you wouldn't need a whole new distribution system.
We burn significant amounts (~30%) of oil for heating and other uses besides transportation.
According to the 2004 annual energy report from the DoE, we consumed about 20.52 quads (1 quad = 1.055 EJ) of petroleum, of which 13.62 quads went into transportation. So you're about right. Only 0.89 went into residential heating, and 0.40 into commercial heating. 0.53 went into electric generation, and 5.08 went into "industrial", whatever that is. It would be interesting to find out if that means materials manufacturing or heating.
But again, what matters is not the total emissions from each fuel, but the incremental emissions for each mile driven by each type of vehicle. The power plant + EV comes out ahead on CO2 even if the power plant is fuele
You say that apart from the battery, electric cars don't require any maintenance. That's a pretty big exception.
As I said, batteries are rapidly improving. The NiMH batteries in the Gen 2 EV1 were predicted to last for the life of the car, but as I said I didn't get a chance to prove it. The Li-ion batteries in the Tesla are projected to last 100K miles, a respectable figure. Those
are reasonable numbers based on expected cycling patterns of existing mass-produced batteries. (200 miles per charge times
500 cycles = 100K miles).
The life of any battery pack can be greatly extended by proper management, including cooling and avoidance of deep discharge cycles.
If you're lazy like me, you often run your laptop on battery power even when you could plug it in, and you do plug it in only
when the battery is about to die. This is not good for battery life, but my laptops and cell phones rarely outlive their batteries anyway.
A car is in a different class. It's a much bigger investment than a laptop, so it'll be easier to overcome that
laziness. An EV with a 200-300 mile range that is plugged in every night is not going to be deep-discharged very often, so the batteries will last quite some time.
Take your sanctimonious attitude and see if you can wire it up to your EV1.
I am really surprised at the outright hostility that this movie about the EV1 seems to have generated in some quarters. People who are normally rational, enlightened and forward-looking turn into know-nothing reactionaries. I really don't understand it.
The Tesla roadster is about $80K, not $100K, but point taken. I have seen a long string of small EV companies appear,
produce a few expensive toys for rich people, and then disappear. I hope Tesla doesn't follow this pattern.
I'm not saying that you should run out and buy a Tesla, but at the same time it is unreasonable to compare the price of a brand-new product and technology still high on its learning curve
with that of a technology that has been mass-produced for a century and has pretty much reached its
technological limits.
As an example of the effects of scale and mass production of EV components, AC Propulsion says they put out a request for bid for a
lithium-ion battery pack. The reply came in at a price 10x what it cost them to make the pack themselves out of commercially available,
mass-produced 18650 cells (the small cylindrical cells used in camcorders and laptops). The bidder had chosen a larger Li-ion
cell that was produced in much smaller quantities.
Clearly it would be much more cost-effective to produce Li-ion batteries in a larger form factor more suitable to
EVs, but that takes volume. So we have a chicken-and-egg problem.
Are you assuming that the electric car will never require service? Where am I going to get that service?
Except for the battery, yes. These cars require virtually no maintenance.
That was certainly my experience with both my EV1s. They never required anything beyond tire rotation
every 5,000 miles, and refilling the windshield washer fluid.
Who Killed the Electric Car? has a cute scene showing all the replacement parts needed by a typical
gasoline car over its lifetime. It was a big pile.
As for batteries, they're rapidly improving. My first EV1 had some bad lead-acid battery modules that required replacement. It originally came
out with a Delphi pack that was a real lemon. GM eventually converted most of the Gen 1 EV1s to Panasonic lead-acid packs
that worked fine. And I never had a single problem with my Gen 2 EV1 (NiMH batteries) in the three years I was allowed to lease it.
"Significant externalities"? I'm making an economic decision, not a political statement.
I can't blame you for making a short-sighted decision based solely on personal economics. But a lot of analyses have shown that once EVs benefit from economies of scale, their total costs of ownership will be less
than those of comparable ICE cars. Problem is, no one has ever let that happen.
But why not lobby for policy changes that take these externalities into account? Do you personally benefit from the
tax credits for 6,000+ pound SUVs?
Oops, I made yet another mistake (but one that doesn't affect my conclusion). The carbon in 1 quad of oil is 19.5e6 tonnes or 19.5e9 kg, not 19.5e9 tonnes. Similarly, the carbon in one quad of coal is 25.76e6 tonnes, or 25.76e9 kg.
These figures come from the
DOE. They publish a real wealth of energy-related
statistics.
That makes the 2004 US carbon emissions from petroleum 782.5e9 kg, and 576.7e9 kg from coal.
That's not my "claim", simply the emperical evidence. Total efficiency, from fuel input to power generation, to power delivered to the wall socket, is only about 30%, as a nationwide average. It's a far cheaper system than lots of little motors, but it's not noticeably more effecient. Nor is it cleaner, when comparing coal to a ULEV car.
I was talking about transmission efficiency being ~94%. You appeared to claim that this figure was about 31%, which is far too low. Thank you for clarifying that it included the thermal conversion efficiency. When I combine the thermal conversion efficiency at the power plant with the real transmission efficiency, then I do get a figure close to yours. (I note a minor error in my previous article, which I wrote late at night. I multiplied the 35% thermal efficiency of a typical coal plant by a 96% transmission efficiency, not 94%. The corrected number is 32.9%, which comes fairly close to yours for fuel-to-wall-outlet.)
But as I showed, that 33% figure is still about twice the average thermal efficiency of an ICE (internal
combustion engine) car. And that's without considering the substantial energy costs in refining and transporting crude oil and gasoline.
Hydrogen just doesn't make any sense. Many have proposed using renewable energy to make hydrogen, or as in your case,
using surplus heat from a thermal (fossil or nuclear) plant. That energy is far better used to make more electricity for the grid, to displace generation from fossil fuels. An illustrative example is the combined-cycle gas turbine. The natural gas is first burned in a gas turbine resembling that in a jet aircraft. Then the exhaust gases, which are still quite hot, are used to make steam for a steam turbine. The overall thermal conversion efficiency is an astonishing 50-60%, a figure no ICE car will ever achieve.
This only works for a gas turbine, where the exhaust gases are sufficiently hot. The waste heat from a nuclear or coal-fired steam plant is at too low a temperature to be useful for cracking water into hydrogen, though it might be used for space heating if it doesn't have to be transported too far.
Hydrogen conversion efficiencies also suck. Electrolyzers are maybe 70-80% efficient, even on an industrial scale, and
auto-sized fuel cells are only about 50% efficient. This makes hydrogen a very poor alternative to the electric grid (94% efficiency) as a means to ship energy.
And the fact remains that we emit more CO2 nationwide from burning coal for electricity than we do from all the oil we burn for all transportation.
First of all, this is not true. In 2004, the US consumed 22.39 quads of coal and 40.13 quads of petroleum. (1 "quad" == 1.055 EJ. I do wish the US would go metric). The carbon in one quad of petroleum (gasoline, actually) is 19.5e9 tonnes, and 25.76e9 tonnes in one quad of coal. Multiplying that out, we get total US carbon emissions in 2004 of 782.5e9 tonnes from oil but only 576.7 tonnes from coal. Worldwide, carbon emissions from
petroleum exceeded those of coal starting in the 1970s.
And even if your claim was true, it would be irrelevant. What matters in this discussion is not the total carbon emissions of coal-fired electricity vs oil-fueled cars, but the marginal emissions for EVs fueled by coal-fired electricity vs cars fueled by oil. I've already shown that they're significantly lower for the EV.
EVs are just stuck as niche vehicles for commuting. The limit on the energy density of chemical batteries is just enough to make a car work, but not for use for cross country driving, freight hauling, construction, shipping, etc, etc.
So what? Commuting may be a "niche", but it's a very big niche. As Ed Begley Jr said at the EV1's "funeral" featured in the movie, the terrible limitations of electric cars make them suitable for only for 90% of the population.
I can't easily find data on how Li-ion batteries perform in cold temperatures, but I do know that they degrade much more slowly at cold temperatures. NiMH and NiCd batteries also prefer to run cold; I know that on spacecraft, where you can control temperatures
with thermal coatings, you usually shoot for temps in the +5C range for maximum life. Only lead-acid batteries really suffer at low temperatures.
In any case, a certain amount of battery heat is created by charging, and normally this has to be actively removed with fans, air conditioning and/or liquid cooling in an EV because the battery pack is physically large and not well connected thermally to the environment. This suggests a fairly obvious way to keep the pack at optimum temperature in cold climates.
As for windshield de-icing, the EV1 had a pretty effective electric windshield heater like those used in aircraft cockpits.
It drew about 1kW, and it quickly got that window hot. I didn't need to use it here in Southern California
except to clear condensation, but I think it would do a good job even in the north.
Air conditioning is also a minor issue. The EV1 heat pump drew about 1-1.5 kW at start, and usually dropped to about half this when the car cooled off. You could also start the AC while still connected to the charger to avoid taking it out of the battery. Compare these drains to the propulsion motor (10-15kW while crusing level on the freeway) and you can see that they're really not very significant in everyday use.
Bingo. We do need a much smarter electric distribution network, especially one that can better accomodate loads like
electric vehicle chargers that don't require constant power.
At the very minimum, we need time-varying electric
rates to encourage people to minimize their consumption during peak hours and shift whatever loads they can to the off-peak hours.
I can easily envision a "smart" EV charger that responds to real-time changes in electric rates by increasing charging
power when electric rates fall, and decreasing power (or even selling back to the grid) when prices rise.
When I had my EV1, I qualified for SDG&E's EV-TOU (Whole House Time of Use) tariff. I also have a grid-tied photovoltaic system on my
roof, so it was quite gratifying to sell much of my solar electricity back to the utility at their peak summer rates. Then, of course, I'd buy it back cheaply in the middle of the night to charge my EV1. Sauce for the
goose, and all that.
Ah, I just saw your other thread. Problem is, your analysis is wrong.
* We generated about 6.33 EJ of delivered electric power from coal, emitting about 1.9 Gt of CO2 in the process.
* We used about 28 EJ of oil-based power for transportation, emitting about 1.8 Gt of CO2 in the process.
* Switching transportation to coal, assuming the car itself was 100% effecient in its use of electricity would more than *quadruple* carbon emission.
First, you're comparing apples and oranges by comparing delivered electricity to the heat input to transportation.
The average thermal efficiency of a large coal plant is about 35%. The peak efficiency of a car engine is perhaps
25%, tops. The average is much less. Just how much less than an EV?
Gasoline has an energy content of about 131MJ/gallon. A gasoline car getting 25 mpg therefore consumes 5.24 megajoules/mile, referred to heat from burning gasoline.
The EV1 got about 4 miles per kilowatt-hour AC, referenced to the wall outlet. That's about 0.9 megajoules electricity/mile. Referenced to heat from burning coal at the power plant, that's still only 2.57 MJ/mile, less than half the consumption of the 25mpg gas car. Remember, I'm not assuming, as you did, that the EV has 100% efficiency. This was a real figure from a real-world EV that included all the losses in the charger, battery, inverter and motor.
That leads me to your second major error: the electric grid is far more efficient than the 31% figure you implicitly claim. The real number for transmission and distribution efficiency in California (where there are some very long bulk transmission lines) is about 94%. Most of that loss is in the transformer outside your house. (And we haven't even discussed the substantial energy costs of refining and transporting oil and gasoline.)
31% is a little closer to the combined thermal conversion and transmission/distribution losses (35% * 96% = 32.9%). But then
you're comparing apples (heat input) to oranges (electricity output) again. Even so, we're still only up to 0.9MJ/.329 = 2.73 MJ coal heat/mile for the electric car, only slightly more than half the gasoline car (5.24 MJ gasoline heat/mile).
So while it's true that coal generates more CO2 per unit of heat than does gasoline, the automotive engine is so vastly less efficient than the power plant + transmission grid + EV combination that the latter still comes out well ahead.
That's just about the most pessimistic assessment you can possibly make of the EV. Combined-cycle gas turbine generators have thermal conversion efficiencies of about 50-60%, and on top of that the CO2 produced per unit of heat from natural gas is less than for gasoline. And don't forget that EVs reduce emissions of "traditional" pollutants (NOx, CO, HC, particulates) far more than they
reduce CO2. And don't forget that not all electricity is made from fossil fuels.
This brings me to our one point of agreement: nuclear power is the way to go in the near future. And, as I think you agree, EVs represent the only way we can apply nuclear power to transportation.
I always love it when people make quantitative arguments using numbers they've pulled out of their ass.
I've done the energy and emissions calculations and analyses many times myself, so I think I know what I'm talking about. Have you? I've shown my numbers, so show me yours. Or are you just parrotting something you heard from Rush Limbaugh?
Re-read what I wrote. There's a ~2:1 daily variation in the load on the electric grid. The grid, both transmission and generation, has to be sized for peak load. That capacity is significantly underutilized at night, and is therefore available for charging very large numbers of electric vehicles.
Nothing says that every single vehicle now on the road must be electric before any of them can be. Just replacing a good fraction of the personal cars used for daily commuting would result in very big reductions in pollution, CO2 emissions and
petroleum imports.
Have you done the actual analysis, or is this just your seat-of-the-pants guess? What estimates did you use for the future price of gasoline and the costs of internal combustion repairs? Have you factored in the significant externalities from the use of internal combustion engines that, by all rights, ought to be taken into account?
Right, the hybrid does overcome many of the problems of the internal combustion engine in urban environments. But all the energy still comes from gasoline, and we need to change that.
I agree that there's a lot of promise in the plug-in hybrid. Most of the benefit will be psychological, to placate those who
want to maintain the ability to drive from LA to Las Vegas on a whim even though they never actually do it.
Once people start to drive plug-in hybrids and realize that their internal combustion engines go unused for many months
at a time, they might become more receptive to the idea of a pure electric vehicle.
Few things annoy experienced EV drivers like myself than those self-appointed experts who pontificate, without any actual experience, that EVs cannot
possibly be useful to anyone unless they have the same range as a gasoline car.
I've read far more than this one analysis. (Have you even read it yourself?) And I've done some of my own, which happen to come to the same conclusion as this one. I cited that particular study because it was so well done.
Nobody expects EVs to replace every internal combustion engine car overnight, so it's a red herring to say that current electric capacity is an obstacle. If EVs are charged overnight, as they are likely to be given time-of-use discounts, grid capacity won't be a problem for quite some time. Furthermore, several groups have looked at EV batteries as a significant source of power during daytime peaks when the cars are parked and plugged in at work. Again given time-of-use pricing, this can actually produce significant income for the EV owner.
You're simply wrong about EVs resulting in 5x the CO2 emissions from coal plants. The actual figure is a 50% reduction in CO2 emissions for the EV even if all their electricity comes from coal (which it doesn't). This is because the coal plant is far more efficient than the small internal combustion engine in turning heat into useful work. That's more than enough to compensate for the higher carbon content in coal.
That said, we need to get electric generation off fossil fuels ASAP. But this shouldn't stop the immediate development and production of EVs, as they can provide significant benefits even with the current electric generation mix.
I did the emissions analysis myself in 1999. I don't think the numbers have changed much since.
The bottom line: Even with present-day power plant emissions, EVs are vastly cleaner with regard to
"conventional" pollutants (nitrogen oxides, carbon monoxide, hydrocarbons, smoke, etc) than ordinary gasoline and
diesel vehicle engines.
With the current electric generation mix, the EV's contribution to CO2 reduction is not as dramatic, but is still
significant. This comes mainly from the considerably greater energy efficiency of the EV. Large power plants running at constant power are much more efficient than small vehicle engines that are constantly throttled.
In other words, the claim that EVs are just "emission elsewhere" vehicles is a myth. But it's a myth that's surprisingly persistent.
And, of course, as electric generation moves to non-fossil sources, EVs will automatically get even cleaner.
The existing electric power infrastructure can support a very large number of EVs, as long as they're charged at night.
Look at the daily electrical load patterns for a large state like California (www.caiso.com). There's almost a 2:1 variation between daily peak and minimum. Today, for example, CAISO is predicting a 49 GW peak at 4pm. Today's minimum was 27 GW at 4 am. The difference is 22 GW, enough to simultaneously charge 1.3 million Tesla cars at 16.8 kW each.
(Caveat: the California ISO area excludes Los Angeles DWP and a few other municipal utilities, so these numbers actully understate total state consumption.)
That said, we do need to move electric generation off fossil fuels ASAP. Nuclear is the best short-term large scale option. Hopefully wind and solar will soon follow. Distributed generation, especially with rooftop solar, can greatly alleviate congestion on the electric grid by producing power close to where it is consumed.
Anything but coal -- yet even if you assume that EVs are charged only coal-fired plants, you're still in much better shape than you are burning gasoline in cars.
So, maybe EVs aren't for you. At least not yet. But that doesn't mean they can't meet the needs of the other 90+% of the population who don't live in Alaska and regularly drive 400-700 miles.
No one vehicle style (coupe, sedan, SUV, pickup, van, etc) can meet everyone's needs. I bet at least some of them don't meet your needs any more than an EV would. So why single out the EV for opposition?
Despite all the hype, hydrogen is actually a terrible choice, both for energy transmission and for vehicle propulsion. It's complex and highly inefficient, and has serious technological obstacles.
The significance of the man-in-the-middle (MitM) attack has been greatly overstated. There's nothing factually wrong with the theory, but a MitM attack just isn't that easy to pull off in practice. The MitM has to remain in the middle to remain undetected; this can be rather difficult when one or both parties is a laptop that connects to many different networks, including the same LAN as the other party.
Solving the MitM problem is 95% of the effort in setting up a secure cryptosystem. So much effort, in fact, that most people don't bother with encryption at all. If we had universally deployed a simple Diffie-Hellman key exchange on every TCP connection, then the NSA's passive eavedropping on IP traffic would be significantly blunted with zero administrative or user effort, or even awareness. (I say "blunted" because the NSA could still perform traffic analysis, and in fact I believe that's their primary goal.)
SSH is a good example of a crypto application that didn't worry too much about the MitM problem and became a huge success as a result. I would really like to see the same technique (cache public key on first connection, warn if it changes on subsequent connections) applied to X.509 applications like SSL and S/MIME. While you might need a third party certification authority when dealing with an online merchant, they're really quite irrelevant for frequent communication within a small, well-defined group of people such as families, co-workers and friends.
I find it amusing (or I used to find it amusing) when people with no practical experience with electric cars pontificate at length about why "everybody just knows" they can never work.
How about asking those who actually drove them every day?
I drove the Smithsonian's car here in San Diego for two years. (Yes, the very same car. See http://www.ka9q.net/ev/). After that, I drove another EV1 for three years.
The EV1 was a great car, a lot of fun to drive, and it met nearly all of my needs. I don't know about you, but none of my other cars could do 0-60 in 7 seconds, and I considered that pretty spectacular. In fact, my gasoline car went unused for so long that I lent it to a friend. I had a charger at home, and I was also lucky enough to have one at work. (Truth be told, I didn't really need the charger at work.) Since those are the two places my car spends most of its time parked, it was nearly always fully charged when I came out to drive it. I never had to go out of my way to a gas station (except to use the car wash), and I hardly ever had the need to drive more than its range in a single day. On the rare occasions I traveled out of town, my EV1 could still take me to the airport. And on the even rarer occasions I needed to drive out of town, my EV1 could easily take me to the local Enterprise lot where I could rent a vehicle more suited to the purpose (such as a SUV for desert camping).
The charge port problem to which you refer was only in the Gen 1, model year 1997, which includes my first car. It was caused by a defective capacitor which had already been removed in the Gen 2 (1999 model year) design. I know of no problems with Gen 2 cars, and I'm pretty sure I would have had there been one.
This is what's so frustrating about having been an EV1 driver: knowing from personal experience just how great a car it was, and seeing others without that experience mouth total gibberish. But I guess we just have to educate people one by one.
As I understand it, zolpidem (better known as Ambien) is not actually a GABA A agonist, but a benzodiazepine omega-1 receptor agonist. That is, while it is not chemically a benzodiazepine, zolpidem hits a subset of the receptors (omega-1, -2 and -3) hit by the less selective benzodiazepines (Ativan, Valium, etc).
The benzodiazepine receptors are located on the GABA A receptor complex, but at a distinct site. Activating the benzo receptors doesn't directly open the chloride ion channel. It simply increases the "gain" of the GABA receptor for naturally produced GABA.
Antidepressants have a similar effect on their targets, though by a very different mechanism. They don't directly activate serotonin (or whatever) receptors, but they increase their sensitivity to naturally produced neurotransmitters.
Drugs that directly mimic natural neurotransmitters (instead of enhancing their action) are generally a bad idea. LSD's effects come from being a potent agonist on a very wide range of neurotransmitter receptors.
Why does everyone automatically assume that providing the ability to make VoIP calls from an airplane will immediately trigger in widespread annoyance and air rage? Airphone was around for years with hardly a peep from anyone. And yeah, I did occasionally see people using them. Why the moral panic only now?
I think it's safe to predict that if you give airline passengers reasonably priced 802.11 access to the Internet, the vast majority will pull out their laptops, check their email and surf the web in silence. Very few will make voice calls. Who really wants to make a voice call in a noisy airline cabin with zero privacy when they have a better way to communicate?
I mean, even on the ground, how much time do you spend on the phone? On your computer?
Disclaimer: I work for Qualcomm, which is developing this air-to-ground technology.
I can't speak to GSM (they're the competition), but power control in CDMA works very well, thank you. In fact, CDMA can't work without it.
In early field testing of CDMA, I noticed that the transmit power from our CDMA mobile fell below the received power from the base station whenever we passed by it on the other side of the San Diego River, a distance of about 400 meters according to Google Earth. Both receive and transmit powers were in the low microwatt range. My standard joke in a customer demo was that we were working on a phone that would run on the incoming RF power from the base station.
So you can be confident that the power levels in a picocell installation on an airplane will be very low.
Disclaimer: in case it's not obvious, I work for Qualcomm.
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That you seem to take a very parochial view of the world. That's okay; it's only human nature. That's why we have governments to inject externalities into individual economic decisions. And some of the most important externalities involve pollution, both "traditional" (e.g., smoke, CO, NOx, etc) and those that cause global climate change.
I don't think an automotive-size gas turbine could come anywhere near the efficiency of a large combined-cycle power plant. I know, for example, that the 500kW gas-fired turbines we have at work produce electricity with only 18% efficiency. The waste heat is used to drive absorption chillers for cooling, which is their primary function. Electricity is just a byproduct. It still works out because the chillers do not require high-temperature heat; they work fine on the cooler exhaust from the turbines.
So if a 500kW stationary turbine only gets 18%, then I don't see how an auto-sized turbine could possibly do better.
I'm still trying to figure out if this really matters. In the coal plants I've read about, the spent steam is condensed at low pressure (60 mb) and 35C or so, so that the latent heat of condensation is released at the lowest possible temperature. Also, there is usually a reheat cycle in which the steam from the first set of turbines is reheated in the boiler and then fed to a second set, presumably at a lower temperature. According to the Wikipedia article on coal power plants, the efficiency of a supercritical steam (540C) turbine plant is about 40-45%, while I compute a Carnot efficiency of 62% for those temperatures. The difference is roughly the same as the 1/3 loss you mention, but it would have to cover all other losses as well.
That just strengthens the case for the EV; I'd been assuming a conversion efficiency of only 35%.
I still don't understand how this can be true. Cracking water into hydrogen requires much higher temperatures than the temperatures at which spent turbine steam is condensed to water (35C). Increasing the condensation temperature would necessarily reduce the efficiency of the turbine. And even if it were true, you'd still be better off burning that hydrogen in another large combined-cycle turbine and making more electricity than sending it through a distribution network to automotive fuel cells that are only 50% efficient.
Who says it has to be their only car? Many families have more than one car, and at least one could easily be electric.
You're exactly right -- that is indeed the proper comparison. And in this case, the power plant + EV still comes out well ahead because of the much greater thermal efficiency of the central power plant. See this quote by Martin Eberhard of Tesla Motors in the recent Wired article:
I don't know what numbers he used to get this exact figure, but it seems about right given what I know about the relative efficiencies of the engines. Especially if the power plant is a combined-cycle gas turbine.
And of course you can make electricity from fuels other than gasoline, which is one of the EV's biggest advantages.
Right again. Cogen heat is also often used for cooling. My company does exactly that at our main campus. We have three 500kW natural gas turbines that produce electricity to offset (but not replace) our grid draw, and the exhaust heat drives the absorption chillers that cool the buildings.
Is this really true? I thought the limiting factor is the temperature of the steam from the boiler. The hotter, the better. Problem is, this is limited by the materials in the boiler (or reactor and steam generator, in the case of a nuke). Also, many large steam turbines use reheat cycles, where the steam coming out of a turbine is passed back to the boiler and used to drive another turbine. Eventually the steam condenses, but as long as this is done close to ambient temperature, the thermodynamic losses are minimized. Can you point me to an analysis?
No matter what you do, producing hydrogen from water takes energy that has to come from somewhere. Any energy you use to crack water could alternatively be used to generate more electricity, i.e., to increase the plant's efficiency. Also don't forget that automotive fuel cells, while better than internal combustion engines, are still only about 50% efficient. Even if the hydrogen were a free byproduct, which it cannot be, you'd be better off burning it locally in a combined-cycle turbine and making electricity at 60% efficiency. Then you wouldn't need a whole new distribution system.
According to the 2004 annual energy report from the DoE, we consumed about 20.52 quads (1 quad = 1.055 EJ) of petroleum, of which 13.62 quads went into transportation. So you're about right. Only 0.89 went into residential heating, and 0.40 into commercial heating. 0.53 went into electric generation, and 5.08 went into "industrial", whatever that is. It would be interesting to find out if that means materials manufacturing or heating.
But again, what matters is not the total emissions from each fuel, but the incremental emissions for each mile driven by each type of vehicle. The power plant + EV comes out ahead on CO2 even if the power plant is fuele
Sarcasm on
Do you have kids? Or do you plan to? Yes? Why, what a stupid economic decision!
We don't have kids, so don't expect me to pick up the bills for your kids' education.
Sarcasm off
The life of any battery pack can be greatly extended by proper management, including cooling and avoidance of deep discharge cycles. If you're lazy like me, you often run your laptop on battery power even when you could plug it in, and you do plug it in only when the battery is about to die. This is not good for battery life, but my laptops and cell phones rarely outlive their batteries anyway.
A car is in a different class. It's a much bigger investment than a laptop, so it'll be easier to overcome that laziness. An EV with a 200-300 mile range that is plugged in every night is not going to be deep-discharged very often, so the batteries will last quite some time.
I am really surprised at the outright hostility that this movie about the EV1 seems to have generated in some quarters. People who are normally rational, enlightened and forward-looking turn into know-nothing reactionaries. I really don't understand it.I'm not saying that you should run out and buy a Tesla, but at the same time it is unreasonable to compare the price of a brand-new product and technology still high on its learning curve with that of a technology that has been mass-produced for a century and has pretty much reached its technological limits.
As an example of the effects of scale and mass production of EV components, AC Propulsion says they put out a request for bid for a lithium-ion battery pack. The reply came in at a price 10x what it cost them to make the pack themselves out of commercially available, mass-produced 18650 cells (the small cylindrical cells used in camcorders and laptops). The bidder had chosen a larger Li-ion cell that was produced in much smaller quantities.
Clearly it would be much more cost-effective to produce Li-ion batteries in a larger form factor more suitable to EVs, but that takes volume. So we have a chicken-and-egg problem.
Except for the battery, yes. These cars require virtually no maintenance. That was certainly my experience with both my EV1s. They never required anything beyond tire rotation every 5,000 miles, and refilling the windshield washer fluid.Who Killed the Electric Car? has a cute scene showing all the replacement parts needed by a typical gasoline car over its lifetime. It was a big pile.
As for batteries, they're rapidly improving. My first EV1 had some bad lead-acid battery modules that required replacement. It originally came out with a Delphi pack that was a real lemon. GM eventually converted most of the Gen 1 EV1s to Panasonic lead-acid packs that worked fine. And I never had a single problem with my Gen 2 EV1 (NiMH batteries) in the three years I was allowed to lease it.
I can't blame you for making a short-sighted decision based solely on personal economics. But a lot of analyses have shown that once EVs benefit from economies of scale, their total costs of ownership will be less than those of comparable ICE cars. Problem is, no one has ever let that happen.But why not lobby for policy changes that take these externalities into account? Do you personally benefit from the tax credits for 6,000+ pound SUVs?
These figures come from the DOE. They publish a real wealth of energy-related statistics.
That makes the 2004 US carbon emissions from petroleum 782.5e9 kg, and 576.7e9 kg from coal.
Um, that should have been 576.7e9 tonnes of carbon from coal. Ooops.
I was talking about transmission efficiency being ~94%. You appeared to claim that this figure was about 31%, which is far too low. Thank you for clarifying that it included the thermal conversion efficiency. When I combine the thermal conversion efficiency at the power plant with the real transmission efficiency, then I do get a figure close to yours. (I note a minor error in my previous article, which I wrote late at night. I multiplied the 35% thermal efficiency of a typical coal plant by a 96% transmission efficiency, not 94%. The corrected number is 32.9%, which comes fairly close to yours for fuel-to-wall-outlet.)
But as I showed, that 33% figure is still about twice the average thermal efficiency of an ICE (internal combustion engine) car. And that's without considering the substantial energy costs in refining and transporting crude oil and gasoline.
Hydrogen just doesn't make any sense. Many have proposed using renewable energy to make hydrogen, or as in your case, using surplus heat from a thermal (fossil or nuclear) plant. That energy is far better used to make more electricity for the grid, to displace generation from fossil fuels. An illustrative example is the combined-cycle gas turbine. The natural gas is first burned in a gas turbine resembling that in a jet aircraft. Then the exhaust gases, which are still quite hot, are used to make steam for a steam turbine. The overall thermal conversion efficiency is an astonishing 50-60%, a figure no ICE car will ever achieve.
This only works for a gas turbine, where the exhaust gases are sufficiently hot. The waste heat from a nuclear or coal-fired steam plant is at too low a temperature to be useful for cracking water into hydrogen, though it might be used for space heating if it doesn't have to be transported too far.
Hydrogen conversion efficiencies also suck. Electrolyzers are maybe 70-80% efficient, even on an industrial scale, and auto-sized fuel cells are only about 50% efficient. This makes hydrogen a very poor alternative to the electric grid (94% efficiency) as a means to ship energy.
First of all, this is not true. In 2004, the US consumed 22.39 quads of coal and 40.13 quads of petroleum. (1 "quad" == 1.055 EJ. I do wish the US would go metric). The carbon in one quad of petroleum (gasoline, actually) is 19.5e9 tonnes, and 25.76e9 tonnes in one quad of coal. Multiplying that out, we get total US carbon emissions in 2004 of 782.5e9 tonnes from oil but only 576.7 tonnes from coal. Worldwide, carbon emissions from petroleum exceeded those of coal starting in the 1970s.
And even if your claim was true, it would be irrelevant. What matters in this discussion is not the total carbon emissions of coal-fired electricity vs oil-fueled cars, but the marginal emissions for EVs fueled by coal-fired electricity vs cars fueled by oil. I've already shown that they're significantly lower for the EV.
So what? Commuting may be a "niche", but it's a very big niche. As Ed Begley Jr said at the EV1's "funeral" featured in the movie, the terrible limitations of electric cars make them suitable for only for 90% of the population.
In any case, a certain amount of battery heat is created by charging, and normally this has to be actively removed with fans, air conditioning and/or liquid cooling in an EV because the battery pack is physically large and not well connected thermally to the environment. This suggests a fairly obvious way to keep the pack at optimum temperature in cold climates.
As for windshield de-icing, the EV1 had a pretty effective electric windshield heater like those used in aircraft cockpits. It drew about 1kW, and it quickly got that window hot. I didn't need to use it here in Southern California except to clear condensation, but I think it would do a good job even in the north.
Air conditioning is also a minor issue. The EV1 heat pump drew about 1-1.5 kW at start, and usually dropped to about half this when the car cooled off. You could also start the AC while still connected to the charger to avoid taking it out of the battery. Compare these drains to the propulsion motor (10-15kW while crusing level on the freeway) and you can see that they're really not very significant in everyday use.
At the very minimum, we need time-varying electric rates to encourage people to minimize their consumption during peak hours and shift whatever loads they can to the off-peak hours.
I can easily envision a "smart" EV charger that responds to real-time changes in electric rates by increasing charging power when electric rates fall, and decreasing power (or even selling back to the grid) when prices rise.
When I had my EV1, I qualified for SDG&E's EV-TOU (Whole House Time of Use) tariff. I also have a grid-tied photovoltaic system on my roof, so it was quite gratifying to sell much of my solar electricity back to the utility at their peak summer rates. Then, of course, I'd buy it back cheaply in the middle of the night to charge my EV1. Sauce for the goose, and all that.
First, you're comparing apples and oranges by comparing delivered electricity to the heat input to transportation.
The average thermal efficiency of a large coal plant is about 35%. The peak efficiency of a car engine is perhaps 25%, tops. The average is much less. Just how much less than an EV?
Gasoline has an energy content of about 131MJ/gallon. A gasoline car getting 25 mpg therefore consumes 5.24 megajoules/mile, referred to heat from burning gasoline.
The EV1 got about 4 miles per kilowatt-hour AC, referenced to the wall outlet. That's about 0.9 megajoules electricity/mile. Referenced to heat from burning coal at the power plant, that's still only 2.57 MJ/mile, less than half the consumption of the 25mpg gas car. Remember, I'm not assuming, as you did, that the EV has 100% efficiency. This was a real figure from a real-world EV that included all the losses in the charger, battery, inverter and motor.
That leads me to your second major error: the electric grid is far more efficient than the 31% figure you implicitly claim. The real number for transmission and distribution efficiency in California (where there are some very long bulk transmission lines) is about 94%. Most of that loss is in the transformer outside your house. (And we haven't even discussed the substantial energy costs of refining and transporting oil and gasoline.)
31% is a little closer to the combined thermal conversion and transmission/distribution losses (35% * 96% = 32.9%). But then you're comparing apples (heat input) to oranges (electricity output) again. Even so, we're still only up to 0.9MJ/.329 = 2.73 MJ coal heat/mile for the electric car, only slightly more than half the gasoline car (5.24 MJ gasoline heat/mile).
So while it's true that coal generates more CO2 per unit of heat than does gasoline, the automotive engine is so vastly less efficient than the power plant + transmission grid + EV combination that the latter still comes out well ahead.
That's just about the most pessimistic assessment you can possibly make of the EV. Combined-cycle gas turbine generators have thermal conversion efficiencies of about 50-60%, and on top of that the CO2 produced per unit of heat from natural gas is less than for gasoline. And don't forget that EVs reduce emissions of "traditional" pollutants (NOx, CO, HC, particulates) far more than they reduce CO2. And don't forget that not all electricity is made from fossil fuels.
This brings me to our one point of agreement: nuclear power is the way to go in the near future. And, as I think you agree, EVs represent the only way we can apply nuclear power to transportation.
I've done the energy and emissions calculations and analyses many times myself, so I think I know what I'm talking about. Have you? I've shown my numbers, so show me yours. Or are you just parrotting something you heard from Rush Limbaugh?
Re-read what I wrote. There's a ~2:1 daily variation in the load on the electric grid. The grid, both transmission and generation, has to be sized for peak load. That capacity is significantly underutilized at night, and is therefore available for charging very large numbers of electric vehicles.
Nothing says that every single vehicle now on the road must be electric before any of them can be. Just replacing a good fraction of the personal cars used for daily commuting would result in very big reductions in pollution, CO2 emissions and petroleum imports.
Have you done the actual analysis, or is this just your seat-of-the-pants guess? What estimates did you use for the future price of gasoline and the costs of internal combustion repairs? Have you factored in the significant externalities from the use of internal combustion engines that, by all rights, ought to be taken into account?
I agree that there's a lot of promise in the plug-in hybrid. Most of the benefit will be psychological, to placate those who want to maintain the ability to drive from LA to Las Vegas on a whim even though they never actually do it.
Once people start to drive plug-in hybrids and realize that their internal combustion engines go unused for many months at a time, they might become more receptive to the idea of a pure electric vehicle.
Few things annoy experienced EV drivers like myself than those self-appointed experts who pontificate, without any actual experience, that EVs cannot possibly be useful to anyone unless they have the same range as a gasoline car.
Nobody expects EVs to replace every internal combustion engine car overnight, so it's a red herring to say that current electric capacity is an obstacle. If EVs are charged overnight, as they are likely to be given time-of-use discounts, grid capacity won't be a problem for quite some time. Furthermore, several groups have looked at EV batteries as a significant source of power during daytime peaks when the cars are parked and plugged in at work. Again given time-of-use pricing, this can actually produce significant income for the EV owner.
You're simply wrong about EVs resulting in 5x the CO2 emissions from coal plants. The actual figure is a 50% reduction in CO2 emissions for the EV even if all their electricity comes from coal (which it doesn't). This is because the coal plant is far more efficient than the small internal combustion engine in turning heat into useful work. That's more than enough to compensate for the higher carbon content in coal.
That said, we need to get electric generation off fossil fuels ASAP. But this shouldn't stop the immediate development and production of EVs, as they can provide significant benefits even with the current electric generation mix.
The bottom line: Even with present-day power plant emissions, EVs are vastly cleaner with regard to "conventional" pollutants (nitrogen oxides, carbon monoxide, hydrocarbons, smoke, etc) than ordinary gasoline and diesel vehicle engines.
With the current electric generation mix, the EV's contribution to CO2 reduction is not as dramatic, but is still significant. This comes mainly from the considerably greater energy efficiency of the EV. Large power plants running at constant power are much more efficient than small vehicle engines that are constantly throttled.
In other words, the claim that EVs are just "emission elsewhere" vehicles is a myth. But it's a myth that's surprisingly persistent.
And, of course, as electric generation moves to non-fossil sources, EVs will automatically get even cleaner.
Look at the daily electrical load patterns for a large state like California (www.caiso.com). There's almost a 2:1 variation between daily peak and minimum. Today, for example, CAISO is predicting a 49 GW peak at 4pm. Today's minimum was 27 GW at 4 am. The difference is 22 GW, enough to simultaneously charge 1.3 million Tesla cars at 16.8 kW each.
(Caveat: the California ISO area excludes Los Angeles DWP and a few other municipal utilities, so these numbers actully understate total state consumption.)
That said, we do need to move electric generation off fossil fuels ASAP. Nuclear is the best short-term large scale option. Hopefully wind and solar will soon follow. Distributed generation, especially with rooftop solar, can greatly alleviate congestion on the electric grid by producing power close to where it is consumed.
Anything but coal -- yet even if you assume that EVs are charged only coal-fired plants, you're still in much better shape than you are burning gasoline in cars.
No one vehicle style (coupe, sedan, SUV, pickup, van, etc) can meet everyone's needs. I bet at least some of them don't meet your needs any more than an EV would. So why single out the EV for opposition?
The battery electric EV, charged from the electric power grid, makes much more sense. See
Carrying the Energy Future: Comparing Hydrogen and Electricity for Transmission, Storage and Transportation
for the detailed analysis.
Solving the MitM problem is 95% of the effort in setting up a secure cryptosystem. So much effort, in fact, that most people don't bother with encryption at all. If we had universally deployed a simple Diffie-Hellman key exchange on every TCP connection, then the NSA's passive eavedropping on IP traffic would be significantly blunted with zero administrative or user effort, or even awareness. (I say "blunted" because the NSA could still perform traffic analysis, and in fact I believe that's their primary goal.)
SSH is a good example of a crypto application that didn't worry too much about the MitM problem and became a huge success as a result. I would really like to see the same technique (cache public key on first connection, warn if it changes on subsequent connections) applied to X.509 applications like SSL and S/MIME. While you might need a third party certification authority when dealing with an online merchant, they're really quite irrelevant for frequent communication within a small, well-defined group of people such as families, co-workers and friends.
How about asking those who actually drove them every day?
I drove the Smithsonian's car here in San Diego for two years. (Yes, the very same car. See http://www.ka9q.net/ev/). After that, I drove another EV1 for three years.
The EV1 was a great car, a lot of fun to drive, and it met nearly all of my needs. I don't know about you, but none of my other cars could do 0-60 in 7 seconds, and I considered that pretty spectacular. In fact, my gasoline car went unused for so long that I lent it to a friend. I had a charger at home, and I was also lucky enough to have one at work. (Truth be told, I didn't really need the charger at work.) Since those are the two places my car spends most of its time parked, it was nearly always fully charged when I came out to drive it. I never had to go out of my way to a gas station (except to use the car wash), and I hardly ever had the need to drive more than its range in a single day. On the rare occasions I traveled out of town, my EV1 could still take me to the airport. And on the even rarer occasions I needed to drive out of town, my EV1 could easily take me to the local Enterprise lot where I could rent a vehicle more suited to the purpose (such as a SUV for desert camping).
The charge port problem to which you refer was only in the Gen 1, model year 1997, which includes my first car. It was caused by a defective capacitor which had already been removed in the Gen 2 (1999 model year) design. I know of no problems with Gen 2 cars, and I'm pretty sure I would have had there been one.
This is what's so frustrating about having been an EV1 driver: knowing from personal experience just how great a car it was, and seeing others without that experience mouth total gibberish. But I guess we just have to educate people one by one.
As I understand it, zolpidem (better known as Ambien) is not actually a GABA A agonist, but a benzodiazepine omega-1 receptor agonist. That is, while it is not chemically a benzodiazepine, zolpidem hits a subset of the receptors (omega-1, -2 and -3) hit by the less selective benzodiazepines (Ativan, Valium, etc).
The benzodiazepine receptors are located on the GABA A receptor complex, but at a distinct site. Activating the benzo receptors doesn't directly open the chloride ion channel. It simply increases the "gain" of the GABA receptor for naturally produced GABA.
Antidepressants have a similar effect on their targets, though by a very different mechanism. They don't directly activate serotonin (or whatever) receptors, but they increase their sensitivity to naturally produced neurotransmitters.
Drugs that directly mimic natural neurotransmitters (instead of enhancing their action) are generally a bad idea. LSD's effects come from being a potent agonist on a very wide range of neurotransmitter receptors.
I think it's safe to predict that if you give airline passengers reasonably priced 802.11 access to the Internet, the vast majority will pull out their laptops, check their email and surf the web in silence. Very few will make voice calls. Who really wants to make a voice call in a noisy airline cabin with zero privacy when they have a better way to communicate?
I mean, even on the ground, how much time do you spend on the phone? On your computer?
Disclaimer: I work for Qualcomm, which is developing this air-to-ground technology.
In early field testing of CDMA, I noticed that the transmit power from our CDMA mobile fell below the received power from the base station whenever we passed by it on the other side of the San Diego River, a distance of about 400 meters according to Google Earth. Both receive and transmit powers were in the low microwatt range. My standard joke in a customer demo was that we were working on a phone that would run on the incoming RF power from the base station.
So you can be confident that the power levels in a picocell installation on an airplane will be very low.
Disclaimer: in case it's not obvious, I work for Qualcomm.