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Electric Cars and Their Discontents
A typical comment about the global impact of switching from gasoline to electric cars on a wide scale comes from reader dbIII, who comments:
"Until something replaces Coal power plants as the main method of generating electricity, you're just replacing one evil for the other."
"With better battery storage it doesn't matter much where the electricity comes from and when - the car could be charging up with solar power in the carpark in the day or with wind when it is blowing, or off-peak when the base load stations are running as low as they can but no-one wants to use the electricity."
"Battery power isn't about saving energy anyway, it's often about shifting the pollution to a big facility that can handle it instead of having heavy pollution control equipment to move about. The first hybrid car I saw, back in 1987, embodied this principle and was designed to work at an underground mine. Above ground it ran on fuel, but below ground you wanted to minimize the air pollution as much as possible so it ran on batteries."
The continued existence of the earth as a habitable planet aside, what about the car itself, and in particular its power source?
Jah-Wren Ryel has a quibble with the terminology used the linked article, writing
"This car is not a true Tesla Car. If it were, it would have no batteries at all. Instead it would gets it energy from some kind of wireless source like microwave power transmission or even the Earth's magnetic field."
Many readers worried about exploding batteries; glowworm was "left wondering if this car is involved in an accident if the batteries will vent like the recent Slashdot articles suggest. Exploding Dells, fires on planes, and soon at an intersection near you... cars venting more flame than the Batmobile."
Reader nSinistrad_D provides reason to think such explosions are unlikely:"Looks like the company that is manufacturing the batteries has replaced graphite with a 'Lithium Titanium Oxide' that they've tested and claim doesn't have the smoking, venting, or explosive problems of normal lithium ion batteries. Here is a link to a rather informative article about the battery technology that will be used in the Tesla. ... I mean, based on the stuff I've read about the founders of the company and a lot of the people who have invested in it (i.e. Elon Musk, Larry Page, Sergey Brin, etc.) I feel I'll wait and see before passing any judgement."
Reader artifex2004 is skeptical: "Here in Texas, where I suspect temperatures exceed battery design, I think this idea will bomb spectacularly. Seriously, though, Li-ion? I shudder to think of how those will get disposed of, eventually."
And Reader Moofie has a tongue-in-cheek solution if the batteries ever go critical: "Maybe you could design a clever little nozzle to get a boost from your on-fire battery packs. That'd be AWESOME."
It's not just safety, of course, that matters to drivers, but practicality for other reasons:
Reader iamlucky13 writes: "15 minutes on the charger might get you another 15-20 miles. And 220 volts at 70 amps is a pretty hefty 15 kilowatts, so to have a dozen cars sitting at the local McDonalds charging is going to be draining about 180 kW from their coinpurse. That is a serious amount of juice. Also, I'm skeptical that you'll be getting 250 miles at 70 mph. If I remember right, electric motor efficiency and power typically increase with load, but fall off with speed, which makes them awesome for say, a 0-60 run in 3 seconds, but marginal at best for high speed cruising. That 250 mile range estimate is probably at significantly lower speeds."
"Big rigs generally run around 5 mpg, but it varies quite a bit around that number depending on the truck, the load, and the speed. Few truckers drive at the most efficient speed because it increases the labor costs significantly."
"If you're suggesting running commercial trucks on electricity, forget it for the foreseeable future. It's definitely been considered. Not only is there the conflicting speed issues I mentioned above, but you run up against the energy density limitations of batteries fast. Assuming the numbers from the article are correct (I doubt it...something isn't quite adding up according to my gut) and unrealistically taking the charge/discharge at 100% efficiency, it's storing up 194 MJ. Gasoline holds about 120 MJ/gallon, so the 1000 pounds of batteries (according to the Tesla website) are equivalent to about 1.5 gallons of gas (6.3 pounds/gal). Divide that an efficiency of around 30% and you've got a 32:1 energy density ratio in favor of gasoline. For a truck to haul the equivalent of 150 gallons of fuel (actually diesel, not gas, but close enough), it would need about 30,000 pounds of batteries. But then you have to go farther and take into account that 2/3's of its cargo capacity has been replaced fuel, so you need to make 3 times the number of trips. And you've got a lot of trucks either sitting idle recharging or having their 30,000 pounds of batteries swapped out every few hundred miles."
"Obviously these are really rough numbers, but other engineers have already looked at the idea in more detail and rejected it."
"I'm not trash-talking the Tesla. It looks like a lot of fun, but like all sports cars, it's a toy and not a good comparison for commercial trucking. Most of a car's weight is itself, be it gas or electric. Most of a truck's weight is it's cargo."
"For the record, I think electric can work extremely well for short range commuting (5-10 miles on city streets), but if you travel far, you'll realistically be looking at gas."
As to the exact number of batteries in the car, reader wbean provides a good reason why it should be exactly 6831: "The motor is going to need a lot higher voltage than a laptop. This means that the batteries have to be organized in series/parallel banks. 6831 is a plausible number since it is 23 x 11 x 3 x 3 x 3. This gives you a lot of flexibility in arranging the banks. You could have 99 banks of 69 batteries in series, presumably giving you something like 345 volts. That sounds about right for a DC motor."
Of course, battery technology is the real crux of the issue; balancing safety, weight, volume and energy density is a tough problem, and as reader loose electron puts it,
"Whoever comes up with a significant advance in battery technology will . Li-Ion batteries have excellent amp-hour ratings for their size, but like all other batteries are still pretty limited."
"Acceleration/Torque for electric cars is not a problem. High performance capabilities are there if you want them. However, you are playing battery energy against performance against distance, and all electrics, or fuel-electric hybrids have been designed to be 'green' in their approach. (Any Hummer owners want an environmentally aware vehicle?)"
"Right now the weakest link in many electronic systems is the energy source. A good solution there and you can be a very wealthy person."
hotspotbloc suggests " a different type of hybrid," one with:- "enough batteries for ~50 miles.
- a small (100cc) biodiesel engine running at a fixed and preset RPM connected to a small generator. The engine would be set to run at the peak of its power curve.
- a small ~10L fuel tank
- and
- an AC charging circuit"
"This is a really old idea. I saw something like this (on a much larger scale) on an USCG cutter (WLB-389) that was built in 1943. Two diesels -> two generators -> one electric motor. Worked great and it could double as a light ship."
Finally, several readers' comments focused on the merits of the particular electric car, rather than only as the embodiment of its constituent technologies.
fermion was one of a handful who talked about the car as a sportscar per se, writing:
"I would wager that this vehicle is more like a Lotus Elise, or a Corvette, or even a S2000, all of which can be had for under 50K. Any performance benefits over those sports cars can be attributed to the natural advantage of this car, namely that you can go from 0-60 without switching gears, and it is easier to get it perfectly balanced without an engine. Anyway, The true test of a sports cars, as opposed to just a fast car, is the handling, which was not mentioned in review. Without proper handling, it becomes a Mustang at 30K."
"Which is to say we are still in the same world, in which low volumes and other issues cause electric cars to be 50%-100$ higher than traditional cars. All that seems to have happened here is that an electric car has been targeted to the high end market and priced accordingly. It is kind of like taking the hummer, putting a cheap truck base on it, calling it an H2, and pretending that it still has the dubious value of the original."
"Oh well, I suppose if they can build a sedan for 35K I would be impressed. We would also have to look at maintenance cost of the vehicle, which would be dominated the battery replacement. A sports car car easily run 20 cents/mile in maintenance. Knowing that laptop batteries can only handle a couple hundred charge cycles, one can image where the long term maintenance cost could approach three or four time that amount."
"I wish we had electric cars. I think the technology is there, and the pricing could be reasonable. But even companies that could be using the electric car to revive themselves, for instance Mazda and Ford, still seem to be married to the antiquated internal combustion engine."
ChronosWS largely agreed with this, writing that "cars like the Porsche Carerra and the Bugatti Veyron (mentioned in a related article) are consummate sports cars -- they exemplify not only speed but styling, handling and quality expected of a car with their price tag. Cars such as the Corvette, especially the most recent incarnation, do so relatively inexpensively. But regardless, 0-60 acceleration is not the most important statistic, and often isn't an important statistic at all except to people who don't know better (I refer the undereducated to the more useful 0-100-0 or 0-150-0 tests, as well as relevant agility tests such as emergency lane change, slalom and skid pad.) Electric cars will be desirable when they meet the following conditions met [by] existing cars:"
- "price (under 30k)
- features (styling, interior, gizmos)
- convenience (fueling in under 5 minutes)"
Thanks to all the readers who took part in the conversation, in particular those quoted above.
The most hotly contested issue raised by yesterday's Backslash was the gratuitous number of Backslashes that have now appeared. In today's Backslash we look at the most insightful comments regarding this issue, and ask; will we find an answer, which we can summarise in tomorrow's Backslash?
"Battery power isn't about saving energy anyway, it's often about shifting the pollution to a big facility that can handle it instead of having heavy pollution control equipment to move about. The first hybrid car I saw, back in 1987, embodied this principle and was designed to work at an underground mine. Above ground it ran on fuel, but below ground you wanted to minimize the air pollution as much as possible so it ran on batteries."
That's really naive. Batteries allow for greater efficiency and decoupling between the power plant and the car. How much innefficiency is there in having lots of tiny little combustion engines zooming all over the place with a bunch of ignorant car owners (I imply we all are ignorant to some degree with our cars) compared to a couple hundred regional power facilities that can use whatever fuel and power generation necessary? They can change to new power and fuel types without affecting the auto industry and consumers. They also can be heavily regulated and monitored to make sure those couple hundred catalytic converters actually work and they are performing proper maintainence to make sure efficiency is maximized and pollution is minimized. I mean.. how many car owners actually care if their cars are a couple of percent off from max efficiency? How many will change their driving style to match the size of engine they bought to squeak out another two miles?
How many of you have been behind a car that makes you gag and you can see the trail of soot in the air for a quarter mile behind it?
People that use such sophmoric arguments are... well.. sophmoric.
Slashdot.. where people join together in deliberate ignorance.
I'd like to see more posts on Slashdot -- discussions distilled down into their component topics, some useful information, and a rehashed go at it again. I hope to see more of these.
On the Tesla, I'd like to see more of those as well. Especially discussion on turbine/electric hybrids. Why are we still using rubegoldberg-styled piston-based engines, with so many moving parts? I would like to see something effective and efficient for my morning commute.
Zhrodague.net - I do projects and stuff too.
Why should the McDonald's pay for charging up your electric car? There's no reason why someone who arrived at the McDonald's by foot be paying some cost of charging up someone else's car. The driver or owner of the electric car should be paying McDonald's (or whomever McDonald's subcontracts or franchises the electric car parking spot) for the electricity. I would expect that any parking spot that would support charging up an electric car to also have some way to charge the driver for money for the electricity, since the whole concept of an electric car is basically going to obsolete the notion of a gas station or e85 station or hydrogen station. Heck, this could even be marketed as a time saving scheme -- you no longer have to go to the gas station because your car will always be ready to go. Unless electric cars start using disposable or at lest removable batteries that can be changed quickly at a 'battery station' for long trips, there's no need to refuel for short-trips.
Electric cars are much more efficient compared to internal combustion engines- much of the inefficiencies and losses pale in comparison to ICE's. Turbines are around 40-45% (BIG turbines), and ICE's are about 30%. I don't have a figure handy for the current state of the art in electric AC induction motors, but it's very high, comparatively. Modern chargers are better, and modern battery packs are more efficient as well (ie how much juice is lost to heat during charging.)
Battery pack technology is a big restraint; one poster in the old thread idiotically said "we don't need better technology, we need stations where you pull up and swap packs!"
Wrong. 1)Lead acid batteries are pretty much the cheapest W/$, but they are HUGE and they weigh so much the vehicle suspension has to usually be modified; they also don't last very long unless well taken care of. NiMH batteries are superior in many ways, except the current patent holder on NiMH packs won't allow companies like Panasonic to sell large NiMH packs for cars. Busses, great, sure. Mid-size sedan? Nope. Why? Probably they want to get nice plentiful royalties.
NiMH is about to be completely eclipsed by Lithium Ion-like technologies. NiMH batteries loose a substantial amount of energy during charging to heat. At least two companies have figured out how to make LiIon more stable (able to withstand charging abuse, physical abuse like getting punctured with a giant steel rod, etc) and charge faster. One of the companies has packs that can be recharged in a few minutes, provided you have a powerful enough charger. Density is better, and they're finding cheaper materials to make them with.
The other big advance has been with motor controller technology and brushless motors; before, people were using industrial-application DC motors which were brushed (which meant PITA maintenance- brushes have to be replaced, you have to have a blower to keep carbon dust from building up inside the motor, etc), inefficient, low-speed, and VERY heavy. Now you've got AC induction motors that produce a TON of power, and really nice inverter systems with regenerative braking and charging built-in.
The main problem with electric cars has always been, and always will be, that nobody is willing to SHARE, and everyone is hideously greedy. Half the industry thinks they'll be the next Henry Ford; the other half thinks someone will figure out how to make a mass-produced vehicle and license their technology for astronomical prices (NiMH patent holders, Tzero with their integrated drivetrain.) Instead, the industry has skipped to LiIon, and Honda/Toyota/GM/Ford have done their electric drivetrain (for hybrid vehicles) development in-house, or worked with industry giants like Siemens.
If you think the new crop of vehicles are different- look in the history books. Every 10-20 years someone gets a bunch of dough, and slaps together an electric vehicle for limited production. It has been going on since the 60's. Even big companies like Solectra have struggled. ZAP! has survived by diversifying, though they're pretty much gone now from the commuter car market now that Mercedes is re-assuming SMART importing in a year or two.
Things seem a little different now though- technology has leap-frogged some previous barriers. The two remaining challenges are market adoption/acceptance, and power generation. MA tried to get a wind farm planted in the middle of a shallow bay, and the fucking environmentalists screamed blue-bloody-murder about everything little thing...from a small diesel tank (1000 gal) for maintenance equipment which was portrayed as the next Exxon Valdeez, to birds hitting the things, to sounds supposedly transmitted into the ocean that woul
Please help metamoderate.
Whoever was objecting to using coal power plants to charge electric cars is overlooking several issues. One, would you rather keep sending billions of dollars to Bin Landenland to power our cars, or to places like Wyoming and Kentucky that have more coal? And that assumes we couldn't offset some of the additional demand with solar, wind and ethanol fueled power plants. Lift the 100% tarrif on sugar from Brazil and free up some of that for ethanol production. Take over part of the Sonora Desert and start using to cultivate oil producing algae. There are a million things we could be doing that we're not.
Kind of reminds me of those rich people back east who opposed a wind power farm because it messed up their view. I was aghast at that. Here we are dependent on a thin line of oil tankers that terminates in a crapass part of the world where people hate us and a lot of the money we spend on oil is quietly funneled to people who want to kill us. Our highest national defense priority should be developing and implementing alternative energy sources and those fat asshats are worried about their freaking view! And some of you are worried about electricity from coal? J*** H Tapdancing C**** what's it going to take before people get a clue? Instead of making energy indepedence a priority our government is spending their billions on a dead-end war in Iraq, finding new ways to spy on Americans and making damn sure a handful of gay people can't get married. Un-f'ing-real.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage