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> One item to consider, Tesla is only going the route of battery powered cars. The majors are investigating multiple different sources, hydrogen, natural gas, c
by bathat 14y ago
> One item to consider, Tesla is only going the route of battery powered cars. The majors are investigating multiple different sources, hydrogen, natural gas, compressed air, battery only, simple hybrid, and series hybrids. So as for stepping up their game I am not sure what you think they need to do.
I don't see how that benefits the incumbents. Unfortunately, the realities of physics and economics (to say nothing about total pollution generated) mean that there are really only two choices: Burn liquid hydrocarbons; or store electricity in a battery (or some combination of the two). Tesla is currently pursing the second option and traditional auto manufacturers are using both. Hydrogen, natural gas and compressed air have all the limitations of batteries and more: The technology that goes in the car is more expensive, the infrastructure is more expensive and exists in fewer places (excluding natural gas), range is short, and 'refuling' times are long.
About ten years ago, as an undergrad, I worked on an NSF- and DOE-funded project to use single-walled carbon nanotubes both as a catalyst in hydrogen fuel cells and for hydrogen storage. Unfortunately, the efficiency gains were minimal, and I'm not aware of much[1] progress that has been made since (but I now work in a different sub-field). That means that a practical fuel cell, big enough to power a lightweight vehicle still costs hundreds of thousands to millions of dollars (mostly due to the requirement for large amounts of platinum to catalyze the H2 in to 2H). Frankly, there has been enough money wasted on pie-in-the-sky projects when there is already-existing technology that works (lithium-ion batteries).
If you don't trust a random stranger on the Internet, then please trust the managers of auto companies. Honda has effectively abandoned their FCX Clairity project because it is cheaper to meet CARB (CA Air Resources Board) requirements by buying zero-emissions credits from Toyota, Tesla, or GM. The FCX, by the way, was a hybrid that only used a fuel cell to meet the average load for electricity and batteries to meet the peak load.
[1] You need at least an order of magnitude better catalyst performance before you can even consider using PEM fuel cells in a mass-produced car. Every time I've seen a press release about better fuel cells, they seem to mention a few percent. At the current rate of improvement, it will take a quarter of a century before we even solve one of the show-stoppers for hydrogen cars.
- effn 14y agoWhat do you have against natural gas? Compressed natural gas/biogas is available today and has been for years, at prices far below that of electric cars, with none of the range and refueling issues that electric cars have.
- grecy 14y agoIf you want to learn more about where it comes from, watch the documentary "gasland". Eye-opening to say the least.
- bathat 14y agoCompressed natural gas (ie, not liquefied) is the runner-up to purely battery electric vehicles. The problems are short range (go read the reviews of the Honda Civic GX: the range is comparable to the middle battery option in a Tesla Model S) and lack of natural gas stations. The second problem can be partially ameliorated by filling at home with a high-pressure compressor (runs on electricity) fed by the same pipe that brings natural gas for your furnace and stove. Unfortunately, that still requires you to plug in the car overnight, just as you would with an electric, because fast high-pressure compressors are still very expensive. The compressor, by the way, costs more than an 80A EVSE for an electric car and adds range more slowly. There are a few public stations that store high pressure gas, but they tend to be at places like airports and taxi maintenance yards, where fleet vehicles congregate (check out Edmund's review of the Civic GX for refill times, though, they aren't nearly as fast as with gasoline). And compressing the gas still requires electricity. It is comparatively easier (and cheaper) to set up an EVSE (the "charger" stand, although it isn't really a charger) for an electric car than to run a gas line and install a gas compressor. The first problem I mentioned doesn't really have a solution with a short time horizon: You need either more volume (a bigger car) or a tank that can hold more pressure (you think that everyone from SCUBA divers to NASA hasn't been working on that one for the last fifty years?). Liquefied natural gas has it's own set of problems: people complain about the Tesla Model S losing a few miles of range while parked overnight, but the boil-off from a cryogenic container would be far worse (an uncovered dewar of liquid nitrogen boils off in "a few" hours; a big 150L dewar at 1 bar will last maybe two or three weeks). It's not that I think natural gas is "bad," it's that as a physicist I can see that we already have technologies that work better (albeit slightly more expensively for now). The only thing natural gas seem to have going for it at the moment is that it is slightly cheaper[1] than a battery-powered car. Unless there is a new and obviously-practicable way to greatly improve the inferior technology in a short amount of time, I don't understand why it is worthwhile to spend money developing it. [1] The Civic GX seems be to only available in jurisdictions (like California) that require a manufacturers to sell a certain number of "zero emissions" vehicles. Thus, it is probable that Civic GX's are "compliance cars" and that Honda takes a loss on each one sold. If you want to know this for sure, wait a few years until the full restrictions kick in and all "zero emissions" cars are required to actually have zero emissions: If the GX is still sold by then, I'll concede that it is a viable product (though I'd still rather spend my money on a something like a Leaf at that price point).