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Old 05-11-2009, 09:04 AM   #75
Bimmerman
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Join Date: Dec 2004
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Quote:
Originally Posted by Darth_Yuthura View Post
And how exactly has hydrogen done any better?
As FCV or IC? Fuel cell hasn't, IC only slightly less so.

Quote:
Originally Posted by Darth_Yuthura View Post
What, do you mean a vehicle with an internal combustion engine and a fuel cell? It's not viable and won't come about if hydrogen is more economic than gasoline. Only when/if it does will hydrogen start to take over and leave gasoline behind.
Nope, the Hydrogen 7 has a fully internal combustion engine that can run on either gaseous hydrogen or pump gasoline. There is nothing fuel cell related there. Hydrogen = / = fuel cell.

Quote:
Originally Posted by Darth_Yuthura View Post
And why would you suggest increasing an already high rate of emissions?
I don't think I am. Hydrogen IC cars clean the air as they drive. The air going into the engine (which is effectively an air pump) comes out CLEANER than it goes in. Wheel to wheel, we should just ride bicycles, as anything with four wheels and manufacturing involved is bad.


Quote:
Originally Posted by Darth_Yuthura View Post
I wasn't astonished, for I was already aware of that. What you claimed is not accurate, however. The efficiency of coal depends upon the type of coal you use. Lignite is among the worst forms of coal to burn, but sometimes it is favored over bituminous because of the presence of other elements (mercury, lead, arsenic, ext.) Bituminous coal is much more cost effective and very abundant, which is why it is used so greatly in the US. Anthracite is the best grade and the 'cleanest' burning coal there is, but it is much more scarce and difficult to mine.
Oooooookayyy. Respectfully, you're confused on the difference between thermal efficiency and fuel consumption. I agree, different types of coal burn with different consumption levels. This is not the same thing as I am talking about. Thermal efficiency is the measure of energy output over energy input to the working fluid. I.e. you have a boiler, a turbine, a compressor, and a pump / radiator. (this is a basic model). The boiler, regardless of what fuel you burn, will produce X MJ of energy. The water is flashed to steam and continues on its cycle through the turbine, compressor, etc.....in no way does the type of fuel, nor the consumption of said fuel, play a role in the THERMAL efficiency.

The oft-maligned ~30% efficiency of an IC engine is the THERMAL efficiency.

The larger a power plant becomes has absolutely no bearing on the efficiency. The increasing number of regenerators, reheaters, intercoolers, etc DOES have an impact, sometimes negative. The amount of fuel burned isn't as important as whether it can reach the needed temperature inside the burner/boiler. Same goes for an engine. It takes X amount of fuel to make X kJ of energy, regardless of the engine. All you are doing to the motor is making it burn cleaner, and therefore less fuel for the same power (kJ/s, W, hp, energy per second = power).


Quote:
Originally Posted by Darth_Yuthura
The US has 25% of the world's coal reserves. That energy provides the majority of the electricity used in the US, but how much of the transportation infrastructure is powered by coal? Except for light rail, subways, electric cars, and hydrogen cars; nothing else uses coal energy.
Do you know how dirty a coal power plant is? The emissions are measured in tons per hour. CO2 emissions from power plants account for 41% of the total US CO2 emissions from all sources. Just because the cars aren't physically emitting doesn't mean they aren't polluters; that energy that creates said CO2 also does the electrolysis of Hydrogen, supplies power to the light rail, subways, and electric cars. Nothing is free.

Quote:
Originally Posted by Darth_Yuthura
Electricity is a means of transmission and can be generated by ANY source of energy you can produce from a power plant. The biggest problem with electricity is that anything depending on it can't function without a link to a power grid. Batteries can only store so much, but take a long time to recharge. Excess electricity from the power grid can't be stored and is wasted, but if that electricity were to be used in ANY way that was beneficial, it would be significant.
I agree in principle. However, the technology for realistic road-trip capable electric cars (not <40 mi ranges, that's pathetic) is a good ways off. Subways, electric buses, and electric trains are really the only good uses, as they follow predictable and planable routes, and have no need to store energy onboard.

Quote:
Originally Posted by Darth_Yuthura
Hydrogen is like that to a degree, but can recharge faster and has a range similar to a gasoline-powered car. Problem is that it takes more energy to produce than is returned, not part of the transportation infrastructure, expensive, and many other issues.
All true. Furthermore, in an internal combustion engine, hydrogen makes significantly more power on less fuel than gasoline does. In simple terms, 600 hp where there was once 450 hp, same fuel economy or better. Granted, that requires tuning, fuel systems changes, etc etc.

What is NOT feasable with hydrogen is converting the cars on the road to run it. Can it be done? Yes. Is it safe or cheap? No. Everyone on the planet agrees that Fuel Cells are the future. In order to get from here to there, we need to embrace a bridging technology--i.e. duel fuel IC hydrogen/gasoline cars. Once the infrastructure (and all the issues with standardizing it are worked out) exist, the hydrogen fuel cell and IC future will happen. Just don't expect it anytime soon.


A racing addiction makes a crack addiction look like a vague desire for something salty. -Randy Hickman

Fear disturbs your concentration. - Sabine Schmitz
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