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Integral
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Wind plants require a LOT of concrete, due to this they start with a CO2 deposit that takes years to climb out of.
mfb said:You cannot stop transporting things. If you just replace the power plants, you still burn 80% of the fuel of today (plus something to account for the increasing demand for transportation).
I think that is the idea. And you would need a lot of power plants to do so. Sure, batteries plus electric motors are more efficient than current cars (as the power plants are rated by their electric output, as far as I see), but that does not change the main conclusion.mheslep said:Finally, if the argument is to be a theoretical one of counting joules as per the IEEE article , then there's little or nothing physically intrinsic to transportation that can not also be accomplished by, say, nuclear power plants charging batteries or synthesizing methane, etc, etc.
rogerk8 said:My idea was originally to make all those wind-mills that already are placed near the sea to produce hydrogen via electrolysis instead of electrical power (while they are so inefficient anyway).
mfb said:I think that is the idea. And you would need a lot of power plants to do so. Sure, batteries plus electric motors are more efficient than current cars (as the power plants are rated by their electric output, as far as I see), but that does not change the main conclusion.
SteamKing said:The problem with electrolyzing seawater is that you can't just split the water molecules apart. You also split the salts apart (primarily sodium chloride), which makes for some nasty waste products. If you want to avoid this unfortunate outcome, you have to purify the seawater first, which adds a lot of additional energy input into the process.
Integral said:Wind plants require a LOT of concrete, due to this they start with a CO2 deposit that takes years to climb out of.
SteamKing said:The problem with electrolyzing seawater is that you can't just split the water molecules apart. You also split the salts apart (primarily sodium chloride), which makes for some nasty waste products. If you want to avoid this unfortunate outcome, you have to purify the seawater first, which adds a lot of additional energy input into the process.
I missed this earlier. A gasoline tank won't explode? You mean it won't explode from pressure as would a structurally failed 3000 psi tank (with whatever inside)? Yes I recognize gasoline needs to be vapor and mixed w/ O2 to explode (as does H2), but there's no need for movie fiction to demonstrate exploding gasoline tanks.mfb said:The plastic tank is safer than hydrogen under pressure. It won't explode (as we are not in a movie). A burning car is bad, but an exploding car is worse.
http://www.nfpa.org/research/fire-statistics/the-us-fire-problem/highway-vehicle-fires in the US. Used to be half a million decades ago.russ_watters said:Car fires are rare enough - I'm not sure I've ever heard of a car explosion happening in real life.
mheslep said:http://www.nfpa.org/research/fire-statistics/the-us-fire-problem/highway-vehicle-fires in the US. Used to be half a million decades ago.
The only relevant point would be fires that did not involve the fuel tank, regardless of the cause. Other components might burn, but no fuel tank, no gasoline/diesel fire.UltrafastPED said:Keep clicking and you find the breakdown by cause:
...
No explosion based on what? Sure explosions are over dramatized in movies but that does not mean gasoline vapors in or escaping from a tank can not explode.mfb said:(but still without an exploding tank).
Without knowing how many accidents there are a year, I cat say if that is rare or not, but it is more than I expected. Still, as pointed out, that wasn't the claim you should be sourcing.mheslep said:http://www.nfpa.org/research/fire-statistics/the-us-fire-problem/highway-vehicle-fires in the US. Used to be half a million decades ago.
I don't assert that 100% of a gasoline tank would explode. Heck it is hard enough to achieve perfect combustion in a cylinder designed for combustion. I don't think any flammable will completely explode unless it is somehow premixed with oxygen, and that goes for H2 as well. What I do expect is that whatever small amount gasoline vapor exists above the liquid fuel will ignite and burn rapidly given an opportunity, leading likely to more spillage of liquid fuel which will also burn if more slowly. Does that assumption require a source?mfb said:There is a huge difference between a small amount of fuel leaking somewhere and burning or exploding, and a full tank of gasoline exploding.
It does:mheslep said:Does that assumption require a source?
The results indicate even more: An open tank can continue to burn, but the fire does not get larger.russ_watters said:Mythbusters did an episode on this. Their results indicate explosions are near impossible.
All I'm claiming is that fire damage can occur on the order of the video I provided above, how 'explosive' that may be I have no idea, and doesn't matter much with respect to the assertion that started this discussion, "The plastic tank is safer than hydrogen under pressure. It won't explode (as we are not in a movie). A burning car is bad, but an exploding car is worse." As far as I can tell that statement is dogma.mfb said:It does:
The results indicate even more: An open tank can continue to burn, but the fire does not get larger.
That's a burning car, it is not an explosion.mheslep said:All I'm claiming is that fire damage can occur on the order of the video I provided above, how 'explosive' that may be I have no idea, and doesn't matter much with respect to the assertion that started this discussion, "The plastic tank is safer than hydrogen under pressure. It won't explode (as we are not in a movie). A burning car is bad, but an exploding car is worse." As far as I can tell that statement is dogma.
OmCheeto said:Does anyone know where I can purchase a 1kw hydrogen fuel cell at the DOE price of $47/kw?
The only one I've found online costs $5685!
I have more experiments to do, in the not too distant future.
etudiant said:The DOE did qualify that to be $47/kW for an 80kW cell in volume production of 500,000 units/yr.
So you may be looking for some extended period.
I'll take several, please, when you find them.
jim hardy said:Folks far removed from the energy industry generally don't grasp the scale.
The world uses around a cubic mile of oil per year.
http://www.theoildrum.com/node/3084 [Broken]
From http://spectrum.ieee.org/energy/fossil-fuels/joules-btus-quadslets-call-the-whole-thing-off
,, "here" referring to this graphic from 'theoildrum'
So start today building a hundred windmills every day.
At end of fifty years, if they last that long, you'd have built enough (about 1.6 million) that you could shut off the oil spigot. Well for today's usage anyway (actually 2006's).
But the first half million you built will be getting might rickety by then...
And that's a technology problem not a political one.
But to the subject of the thread -
Hydrogen is awful stuff to handle. I would not ride in the same car with a bottle of 3000 psi hydrogen .
I do like the fuel cell idea when coupled with H2 production by reducing water with aluminum.
http://www.alumifuelinternational.com/company.html [Broken]
old jim
Does it matter? The non-fuel uses, chemical feed stocks and the like, are a relatively small fraction of the total.enosis_ said:Is this oil usage estimate strictly for fuel - or all uses?
Fuel-cell technology is a type of renewable energy technology that converts chemical energy from a fuel, such as hydrogen, into electricity through an electrochemical reaction. It is considered a clean and efficient alternative to traditional fossil fuel sources.
Fuel-cell technology is important because it offers a sustainable and environmentally friendly source of energy. It also has the potential to reduce our dependence on fossil fuels and help mitigate the effects of climate change.
Fuel-cell technology is still in development and has not yet been widely adopted as a mainstream energy source. However, there has been significant progress in research and development, and it is being used in certain applications such as transportation and power generation.
Fuel-cell technology offers several benefits, including zero emissions, high efficiency, scalability, and versatility in terms of the types of fuels that can be used. It also has the potential to reduce our dependence on foreign oil and create new job opportunities in the renewable energy sector.
Some of the challenges facing fuel-cell technology include high production costs, limited infrastructure, and the need for a steady supply of hydrogen. There is also ongoing research and development to improve the durability and performance of fuel cells, as well as to find more efficient and cost-effective ways to produce and store hydrogen.