What is Digg?108 Comments
- samotage, on 11/06/2008, -0/+28I wonder if a joule of electricity that goes into making hydrogen, then converting this back into electricity via the fuel cell and moving the the vehicle is as efficient as the same joule of electricity stored in a battery turning an electric motor and moving the same vehicle?
- BoneheadFarker, on 11/06/2008, -0/+12Probably not. But the difference is that a hydrogen fuel cell can be refilled within 10 minutes, where recharging the battery pack will take hours. This will be the real deciding factor between electric and fuel cell vehicles.
- UselessTrivia, on 11/06/2008, -0/+10Kinda sorta. You have to think about it from end-to-end.
In your example, the battery will almost surely win in terms of converting stored energy into kinetic energy. But where did the energy to charge the battery come from. Nuclear? Coal? Hydro? That makes a big difference. Likewise with Hydrogen, how you capture the hydrogen has a big impact on its efficiency as well.
The easiest way to get hydrogen is to break down hydrocarbons (fossil fuels) which in most instances is close to pollution-free, but isn't solving our dependence on non-renewable fuel. You can break down H20 into components with electrolysis, but again that energy has to come from somewhere. Best case is solar, wind or hydro, but again it could be coal or nuclear (nuclear is NOT an unlimited resource...we'll run out of Uranium eventually too).
The second law of thermodynamics is a real bitch. No free energy. - Okinsley, on 11/06/2008, -0/+10I don't believe it is. If you look around and do some math, I believe it was around the 70-80% efficiency mark.
so you lose 20% of the power of hydrogen just to make it mobile in your car. - hamobu, on 11/06/2008, -0/+10To all you who say that bateries are more efficient. They are, but efficiency is just one of the criteria.
- NonLeftistDiggr, on 11/06/2008, -0/+6awesome, can it help reduce the astronomical amounts of electricity required to generate burnable hydrogen gas?
- JekJob, on 11/06/2008, -0/+6Hydrogen is the most abundant element in the universe. I don't think we'll run out.
- 4321234, on 11/06/2008, -0/+5So if the process of charging a battery gets you a 90% return from the efficiency of that process, then you beat hydrogen by 10%. Now subtract whatever percent you lose from lugging around the extra weight of those batteries.
- Prism123, on 11/06/2008, -0/+4with out current wasteful usage of uranium and our current reserves yes we would run out fairly quickly if we drastically increased nuclear power, but with proper nuclear waste recycling like they do in france, we won't run out of uranium anytime soon, also we could extract uranium from less conventional sources(such as ocean water) which are more expensive but would provide enough uranium for a very long time.
And that's only fission. If fusion power becomes economically and technologically viable(still a few decades away but we are making progress) we'll have enough power for far longer than the amount of time it will take our sun to transform into a red giant and eat the earth.
solar energy comes from the sun, which runs on nuclear fusion btw
We should still be heavily investing in solar and wind, I'm just saying nuclear can be a near unlimited energy source if done right. - MalarkeyPN, on 11/06/2008, -0/+4That's one problem solved. Well, at least alleviated somewhat.
Now where will all the hydrogen come from? - BESTenemy, on 11/06/2008, -0/+4This article will answer all your questions:
http://www.physorg.com/news85074285.html - UselessTrivia, on 11/06/2008, -0/+4Battery improvements are also just one piece of the puzzle. Higher capacity is coming. Faster charging is coming...but the power grid in most places simply isn't capable of the output necessary to charge a car in 3-5 minutes. You need something like a 1+ MW/hr output to do that, and typically only substations carry that kind of load.
- Eccentric1, on 11/06/2008, -1/+5This is not new. There's a company with patents and a great deal of work already done in this area. They plan to market conversion kits for cars.
http://www.switch2hydrogen.com/h2.htm
Our Hydrogen Conversion Kits accomplish the task by using a solar array or wind turbine (or both, depending on customer's physical location) to power the Hydrogen Generator. This home Hydrogen generator remains in your garage and is about the size of a dishwasher.
The Hydrogen generator connects to your water line and the solar array (or wind generator) provides the necessary power to run the generator.
When you park you car in the garage at night, you plug your car into the generator.
Using the available pressure in your water line, the Hydrogen Generator pumps the Hydrogen it has produced during the day into the Metal Hydride storage tanks in your vehicle,
safely storing the gas until you're ready to drive. - BoneheadFarker, on 11/06/2008, -0/+4@demilio
The only problem with that is what do you do when you go on a trip and have to recharge after 6 hours on the road? You can't just pull off the road every 6 hours and recharge for 8. It's a good idea for the commuter who can get to work and back on one charge. But for long trips, purely battery powered vehicles are impractical. A hybrid fuel cell/battery powered vehicle would be a very good comprimise though. - KingGorilla, on 11/06/2008, -2/+6Stop telling me these beautiful lies
- GSnake, on 11/06/2008, -0/+3Batteries overall are just too far back for current needs. It's not to say that there won't be major advancements in battery development, but I don't think batteries have even scratched the surface of their potential.
Hopefully in the next 10-15 years we start seeing major innovations with storing energy. - Carnage6669, on 11/06/2008, -0/+3not everybody has a garage... lots of people live in apartments that have car-ports... hence no charging at home
- cubicledrone, on 11/06/2008, -0/+3Amazing what happens when you pay smart people to think up cool *****. We used to do that in America about 50 years ago. We don't any more. That's why our most successful companies sell patio furniture.
- theadvinci, on 11/06/2008, -0/+3I had exactly the same thought.
- Drakoi, on 11/06/2008, -0/+3DUDE, DON'T LINK TO THE BLOG, LINK TO THE FRICKEN ARTICLE.
http://www.sciencecodex.com/hydrogen_tank_lighter_ ... - JekJob, on 11/06/2008, -0/+3That's true, but I think it's relatively simple to extract hydrogen from water. I remember somebody did it for the science fair when I was in elementary school - just need some water and a few 9-volt batteries.
I see no reason why a hydrogen plant couldn't be powered by solar or wind energy. - dharasick, on 11/06/2008, -0/+3and 60% more expensive!
- MalarkeyPN, on 11/06/2008, -0/+2Okay, that sounds pretty sweet.
- UselessTrivia, on 11/06/2008, -0/+2The hydrocarbon reformation process isn't pollution-free in and of itself, but if you do it in a plant rather than the car itself, you have the opportunity to sequester the CO and CO2 byproducts rather then exhausting them into the atmosphere.
- cubicledrone, on 11/06/2008, -1/+3Take a look at a picture of Earth from space. See the blue parts? There you go.
- 4321234, on 11/06/2008, -2/+4Don't forget to ask how many joules it takes from your AC source that you charge your batteries from to get X number of joules out of those batteries.
- GSnake, on 11/06/2008, -1/+3I'm not really too sure why they're even bothering with hydrogen. Why not just put most of the money in improving battery technology?
- UselessTrivia, on 11/06/2008, -1/+3I'm a fan of hydrogren...but am I the only one that worries that all the water vapor our cars will be putting out will just cause different kinds of ecological problems than carbon?
I envision cities perpetually covered in fog. - mchristiansen, on 11/06/2008, -0/+2The idea of using the grid's off-peak hours to produce hydrogen for all of those parked automobiles seems like a good idea. But we would need to produce that much more electricity assuming that Solar or Wind is not available .
- MalarkeyPN, on 11/06/2008, -0/+2Well, fine. But you do have to isolate it from rest of the universe before you can put it into a fuel cell. That takes electricity and as of now most electricity is produced by coal, which kind of defeats the purpose if you're thinking hydrogen cars are clean.
I'm not saying it's hopeless. I'm just looking at a different hurdle. - Phalanxia, on 11/06/2008, -0/+2That's not the only problem. It's been proposed that if a hydrogen tank exploded in a tunnel, it would create a fireball which would exceed temperatures of 2000 Celsius, and due to the cramped conditions would cause other hydrogen cars to explode, creating a maelstrom that would blow out both ends of the tunnel, and cause the columns holding up the structure to melt, and whatever mountain is above would collapse into it
- InfiniteNothing, on 11/06/2008, -0/+2By far not the worst "magic energy from water" idea I've heard! The only downside is that the Sun and Wind really don't produce that much energy compared to say a tank of gas.
- InfiniteNothing, on 11/06/2008, -0/+2Generally it is less efficient because you have to compress the hydrogen. Fillability is the main benefit. The best of both worlds is to store the energy as methanol and either fuel cell that or just burn it.
If the alloy can absorb fast and dense enough, it might be a good option too. - Slovenian6474, on 11/06/2008, -0/+2Price?
- jonshipman, on 11/06/2008, -0/+2Fog that completely eradicates chapped lips and dry skin?
Don't let the lotion/chapstick companies know about this! - jorisb, on 11/06/2008, -0/+2A real battery replacement technology is ultracapacitors. The first cars and busses are coming next year.
They are lighter, charge much faster (minutes), and last longer than lithium batteries.
http://www.cleantech.com/news/3174/eestors-weir-sp ... - BESTenemy, on 11/06/2008, -0/+2 Notice the careful selection of words: "60% lighter than the amount of batteries required to power a car". No mention of an "electric car". They do look at Toyota Prius, but that is a hybrid where in addition to batteries the car has to carry the weight of the gasoline engine along with fuel. Hybrids are inefficient due to the fact that they carry 2 engines and 2 sources of power only one of which is being utilized at any given time, while the other one acting as payload.
If the article drew comparison between a hydrogen car and an electric car, the figures would've been different, or if the hydrogen car had to carry a gas engine and a tank of gas along with it, much like a hybrid.
In reality hydrogen vehicles may be more efficient than hybrids, but are inferior to battery powered EV's. - thcobbs, on 11/06/2008, -0/+2Not to mention.... how do you get the hydrogen OUT of the tank if its readily absorbed?
- darkciti2, on 11/06/2008, -0/+2Isn't magnesium highly flammable?
- vilago, on 11/06/2008, -0/+2geothermal is a very underrated resource. iceland is basically sitting on top of a volcano. if you could use that heat and flash liquid water into steam, you could power turbines that electrolyze water and create hydrogen pollution-free and oil free.
- Slovenian6474, on 11/06/2008, -0/+2Sure it can be done, but how many of us can afford a car that cost as much as those made for racing?
- mchristiansen, on 11/06/2008, -0/+2Wow. Exon shareholder must be out in force for this article. All the comments about burning hydrocarbons to extract hydorgen from water. Hydrogen extraction is a perfect application for wind or solar power. Place wind generators in the northern regions where its flat and windy, extract and ship the H2 down the the rest of the country in piplelines. Same is true for the southwest for solar.
- Quaterni0n, on 11/06/2008, -0/+2At the moment, hydrogen can't compete, but never say never.
- Slovenian6474, on 11/06/2008, -0/+2I'm sorry, i thought we were talking about making the current 2 ton vehicles lighter with these wonderful (and equally expensive) composites and plastics you were talking about. Not re-tooling NA for hydrogen.
My point is that it's MUCH cheaper to produce a 4000lb car and have it get worse gas mileage than to make it of more expensive material - thcobbs, on 11/06/2008, -1/+2or you can used the steam to also do high-temperature electrolysis that is far more efficient as you get a good deal of the energy needed to separate from heat.
- 4321234, on 11/06/2008, -0/+1And as we use it up for fuel, the distance between places gets shorter.
- 4321234, on 11/06/2008, -0/+1Fuel cells convert hydrogen to electricity right inside the fuel cell.
- BESTenemy, on 11/06/2008, -0/+1@4321234
The reason for hydrogen transportation inefficiency is not due to the fact that they can't make the fuel tanks light enough. It's the hydrogen itself - the synthesis, compression and re-composition that are wasteful. It's a dead end solution long before you get to the question of "where to put it".
In addition, electrochemical cars offer the benefit of regenerative breaking - the ability to quickly convert energy back into electricity for storage in the same batteries it came from. Hydrogen cars would have to store the exhaust (water) and use additional components for rapid electrolysis and compression to mimic regenerative breaking, but as the process would be equally wasteful as the initial conversion cycle, the efficiency of regenerative breaks in a hydrogen car would be zero.
We have better technology here today.
The only reason hydrogen is getting the hype cause its distribution resembles gas distribution. To get hydrogen you'll have to go to the gas station. Battery powered cars you can charge yourself.
As I said it in the past, the industry is facing the same challenges that the music industry did going into the digital age. They tried preserving the old distribution system, alienating users that were in favor of downloading content.
The same stubbornness generates the hydrogen tech hype. The car companies want to preserve vehicle complexity to keep the need for frequent maintenance. The oil companies want to keep customers at the same gas stations. Today's Exxon oil will be tomorrow's Exxon Hydrogen. They don't care what the fuel is and how wasteful the process is, as long as they get to sell it. They will pass the cost onto the consumer, so their bottom line will be the same. - chongli, on 11/06/2008, -0/+1The EEStor supercapacitor stores 2-5 times as much energy as a lithium ion battery and charges in 5-10 minutes.
Once it comes out, hydrogen cars will be forgotten.
http://en.wikipedia.org/wiki/EEStor - 4321234, on 11/06/2008, -0/+1That's todays tech. The treehugger article says 60% weight savings and that's one breakthrough. Maybe a couple more big ideas and we'll be there.
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