Article on the supercapacitor bus on trial in Shanghai
Posted on 12/12/2006 3:37:49 PM PST by alnitak
Oh, for Pete's sake. The whole "hydrogen economy" is speculation, but that doesn't deter you! In the time I have left on earth I will probably drive an electric or electric/internal combustion hybrid. Hydrogen car - not!
How about ultracapacitors instead? They're getting to the point of having the same energy density of batteries, but they take just seconds to recharge. MIT is fast developing these. And there are prototype buses running in Shanghai using supercapacitors. They recharge at scheduled stops, and can do so in the time it takes to load and unload passengers.
If these can achieve a range equivalent to a normal electric car (70 miles or so), they'll take away one of the primary drawbacks of electric - a shorter range and a long recharge time. If you can get to 150 mile range, will it really matter if you have to stop every two hours on a highway trip to recharge for a minute?
Not speculation. There are buses powered by supercapacitors on the road in Shanghai.
We already live in the Hydrogen economy, and we already have the optimum transport method: chains and rings of Carbon.
Hobbyists are already modifying hybrids so they can be charged by a wall outlet.
Hobbyists are already modifying hybrids so they can be charged by a wall outlet.
See Post 25
Nope. Every part of the hydrogen economy is already proven technology today--with the one exception of the energy source. Electrolysis cells have been around for a couple of hundred years. Fuel cells are newer, but, except for ones sufficiently small and light for transportation use, are also well-tested. Pipelines (including for hydrogen use) are also well known.
"Supercapacitors" using "nanotechnology" are interesting research concepts that "may" pan out, but are not in the same class as the above.
Link to proof, please. I've been following the alternate energy business for a LONG time, and all the info I've ever seen on "supercapacitors" is that they are very much in the research stage. I've certainly never seen any info on technology mature enough to power something like a bus.
I suspect you have supercapacitors confused with fuel cells. There "are" fuel cell powered buses. The main company behind THAT technology is Ballard Energy Corporation.
See post #50.
These are supercapacitors, NOT fuel cells.
I found another article on the same subject, and it's not quite the glowing success your link paints.
And the way the technology is being used essentially proves my point. "Supercapacitors" just do NOT store sufficiently large amounts of energy to be practical. In this application, they basically have a re-charging station at every bus stop--drive the bus the two blocks from one stop/re-charging station to the next, and then "recharge" the "supercapacitors". The buses are slow, both in movement and in recharging. The passengers actually preferred the old electric buses with arm connections to overhead wires.
Contrast this with a REAL energy storage device--you fill the fuel tank at the bus depot, drive all day, and refill the fuel tank when you get back to base. Diesel buses and fuel cell buses both yield that kind of performance. Supercapacitors do not.
Don't expect "supercapacitors" in the family car anytime soon.
Existing H2 cars have longer range, higher performance, and fast refills. If supercaps can beat that, fine, whatever. But the attitude that somehow H2 is some evil demon that must be defeated, as it appears some have, just baffles me. Perhaps it's merely becuase Geo. Bush brought the subject up, and some feel the need to defeat him. If so, that's a lousy reason to reject a technology the could be very valuable. Bush is gone in 2 years, and we'll have to live with our technology forever. We should choose irregardless of politics.
To be clear - I'm not arguing against H2. But there are technological challenges to be overcome that I do not see as being any easier than the challenges facing ultracapacitors. When you compare H2 to ultracapacitors, I think you'll see an advantage to the capacitors if production cost is similar. Why? The basic infrastructure to recharge ultracapacitors is already in place. Yes, it will need upgrading. But why generate huge sums of electricity to make H2 when you can use the electricity directly? I don't see H2 being a better choice if you can develop the capacitors at a similar cost per vehicle....
H2 can burn in regular internal combustion engines, Mazda is selling one in Japan today. It will be hard to beat that fact for initial cost, transition costs, and ease of use.
The basic infrastructure to recharge ultracapacitors is already in place.
As is the infrastructure for H2, because its the same. An interesting scenario for H2 is producing it with small machines at the fueling site, perhaps even in your home with proper precautions. It's true that high temp reactors could produce it more efficiently, but costs and difficulties for transport might negate that. We have power and water going to fueling stations today, and installing a small H2 production machine might be more effective and faster to ramp up.
But why generate huge sums of electricity to make H2 when you can use the electricity directly?
If you know about how electric grids operate, you know that peaking plants must be brought up on-line every day. Indeed, the reason why electric companies sold cities and individuals on the idea of street lights was to enable them to get money for electricity that would otherwise be wasted. The efficiency of base load plants over peaking plants is several times. If you increased the base plant generation by a small percentage, and used it at night to generate H2, you eliminate the necessity for peaking plants, and get a leg up on whatever inefficiencies exist in power storage via H2.
Supercaps charged right before use don't have that advantage, and actually make the base vs. peak generation situation worse.
But why generate huge sums of electricity to make H2 when you can use the electricity directly?
You will never be able to use electricity directly in a vehicle. Some energy storage medium *must* be used, and all of them have inefficiencies.
WTF??
The planet is three-quarters covered in water; it doesn't have to be potable to extract hydrogen from it. More fundamentally, the use of hydrogen as fuel would not deplete the total water supply in any case -- when you burn hydrogen, it becomes... wait for it... DIHYDROGEN OXIDE, otherwise known as WATER.
The original supply of energy is a separate issue -- if "the hydrogen economy" works out, hydrogen would be used as an energy storage medium, not an energy source. It may turn out that some other energy storage medium will be more practical (an issue the author addresses elsewhere in the essay, but at severely compromised credibility after this stupid boner).
Precisely. As I noted in my previous message, it's hard to take somebody seriously after they make a mind-numbingly stupid assertion, even if they're right about other issues.
Emissions during its creation offset any value of zero emissions during use...unless you happen to be in a space craft or submarine where zero emissions is life or death. The emissions will come from energy sources employed to create the hydrogen. Oil, natural gas and coal are the prime sources now. Hydroelectric and nuclear are the lowest producers of emissions. Hydrogen is a niche market. Cherry picking the emissions during the "use" phase vs the "generation" phase is disingenuous.
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