Scientists Say Hydrogen Could Be "easily" Produced From Water And Sunlight

[Guest]

Chicago (IL) - Hydrogen shapes up to become one of the most important fuels for the future, but scientists need to overcome substantial hurdles to enable an efficient production of hydrogen.

Scientists Say Hydrogen Could Be "easily" Produced From Water And Sunlight : Read more

 

[Guest]

What will we drink if we use water for fuel?

 

[martel80]

[citation][nom]Waterboy[/nom]What will we drink if we use water for fuel?[/citation]Alcohol.

 

[Guest]

Water.

The water isn't destroyed when it's used for fuel... and the energy cycle that nobody seems to talk about is the exact reason why these sort of articles don't make a bit of sense.

You CAN create hydrogen from water... just add a lot of energy and the Hydrogen will split from the Oxygen. Gather up the Hydrogen and you can burn it to generate heat. The point that for some bizarre reason articles like this seem to miss is that when you "burn" hydrogen you're really just adding back in the oxygen to recreate the water that you started with.

If we had some efficient/affordable way of storing hydrogen (we don't) then this cycle COULD be very useful. We could use stationary "Hydrogen generation systems" that sat at our homes and spent the day generating hydrogen from water and sunlight. Then at night we'd 'fuel up' the car by transferring the stored Hydrogen into the vehicle to be used the next day to run the car. It's possible that someday this sort of system could be VERY feasable.

What makes no sense AT ALL is the idea of pumping water into our gas tank and 'running' the car on water. The generation of Hydrogen from water absorbs MORE energy than the burning of it generates (Second Law of Thermodynamics). If we had some way of generating all that energy in the vehicle then we wouldn't need the damn water in the first place... it'd just add a pointless layer of conversion and loss of efficiency. The ONLY thing the extraction of Hydrogen from Water does is give us a way of storing energy. It's the equivalent of a battery, not a gallon of gas.

 

[Guest]

So... the summary is that there are quite a few ways of generating Hydrogen from water, and the important variable is not is it "Easy" (silly metric for a chemical process)... but rather is it EFFICIENT.

The point this article misses is that this guy isn't adding ANYTHING toward the solution of the problem... because the problem is not creation of Hydrogen for use in vehicles... but rather the reliable STORAGE of Hydrogen in vehicles. Once the storage problem is solved the largest hurdle to mainstream use of Hydrogen vehicles will have been overcome.

 

[Guest]

Bull****
Very nice if they find a method to split water more efficiently, but there is not much point in splitting water and then combining it again in the same car.
For this to be effective your electrolysis efficiency X efficiency of converting Hydrogen to water (be it by burning or fuel cell tech) has to be higher then the efficiency of photovoltaic cells.

 

[Guest]

As stated in other comments conversion of water into hydrogen takes a lot of energy. The other item with the 'hydrogen economy' is the fuel cells. A resent article said that a vehicle's average fuel cell's life is 50,000 miles. Battery powered cars have a much longer life expectancy and yet many people will not buy them because of the pending cost to replace the batteries. I doubt that cost to replace a fuel cell will be cheap.

The only other ready source of Hydrogen is Natural Gas, Like That Is Commodity Is Not Expensive Enough!!! Cute Idea, just not ready for prime time.

Photo volt roof panels on every house. Windmills all over the country and MANDATING the replacement of most lighting with high efficient LED color corrected lighting would collapse the electrical usage America now consumes. Build electric mass transit system all over the country and people will move a lot of their transportation to pure electric powered. Mandate energy efficient new construction and help owners of older homes and business insulate the existing structures.

 

[Guest]

PV is coming, and IMO affordable durable photovoltaic cells for stationary small plant power generation (as in 'on your house') is the technology with BY FAR the best chance of providing much of the world with renewable power.

The problem is that to efficiently leverage that sort of generation requires huge changes to the power grid. The 'grid' is currently designed for production that's concentrated at Large Powerplants and distribution to many small customers. It would not cope well with millions of small producers pumping onto the grid. To accommodate this fundamental change will require huge changes to the distribution system, and the creation of entirely new types of powerplants... like storage plants that efficiently store up energy produced during the day and release it at night.

Right now each homeowner generating their own power with PV cells needs to have expensive and limited lifespan batteries to store charge... move that storage function to the utilities and it opens up a lot more options for HOW to store the energy. The problem is that Utility companies don't seem to have any interest in this, they like the system the way it is... with them having full control over what is generated and where. It doesn't help that they are defacto monopolies with zero incentive to change their ways. The Government is going to have to FORCE them to make these changes, otherwise they're going to do everything in their power to dissuade individuals from generating their own power.

 

[the_taker]

What happens if the catalyst molecule is not used up or rendered inert when it comes into contact with a lake or an ocean?

 

[bounty]

nah, just more cheap effecient solar cells. The utilities thing would sort itslef out. PV works best during peak utilization anyways, then hydro etc can keep your router working at night. And if you had enough cheap effecient solar, you could push water uphill with all the spare power, then hydro it at night.

 

[Guest]

@the_taker : I'm sure the catalyst is captured... similar to the design of a Catalytic Converter where the platinum is bound to a ceramic substrate.

@bounty : Yea PV does have the advantage of being available when demand is highest, but it will still require fundamental changes in the power grid to scale from the current state (a few crazies paying tons for solar so they can say they have it) to broadly applied (millions of people providing a significant percentage of supply requirements on a dialy basis).

The hydro idea is one that folks have mentioned... it's an interesting practical solution to the storage problem (where a large body of water is available at least). It's also a good illustration of the advantage of scale on the storage side (individuals would have a tough time using this solution) and the change in mindset required by the utilities (hydro is for making power not storing it!).

 

[spuddyt]

so basically, the energy itself comes from sunlight, gathered slowly, and slowly "storing" that energy by making the hydrogen, then when you want that energy back again, simply ignite the hydrogen and off you go, releasing all the energy you slowly gathered from the sun before

 

[CannedTurkey]

[citation][nom]Waterboy[/nom]What will we drink if we use water for fuel?[/citation]
Brawndo http://www.brawndo.com/It's got electrolytes.