Mike Strizki Solar Hydrogen

abmedlin
By abmedlin on Sun, Aug 16, 2015 - 9:11am

Hi,

Just joined this group this morning.  I was wondering if anyone is familiar with this guy talking about solar hydrogen. https://www.youtube.com/watch?v=0bXNjTUtMf8   

 

Thanks

 

Alan

5 Comments

Jim H's picture
Jim H
Status: Diamond Member (Offline)
Joined: Jun 8 2009
Posts: 2379
Creating Hydrogen with Solar Electricity

Elon Musk talks about the issues here, starting at the 10:30 mark;

As I understand it, and this has been something I have watched for years, the step where the inefficiency exists is in the electrolysis itself.    Researchers have been working on better catalysts, but to my knowledge there is not a good, commercial solution yet that provides for high efficiency in the wafer --> H2/O2 conversion step.

Here is some discussion of the research;

  http://www.technologyreview.com/view/512996/a-cheaper-way-to-make-hydrog...

....A commercially viable electrolyzer is considered a key component to the long-sought hydrogen economy. A good catalyst can lower the amount of electricity that is needed to produce hydrogen and oxygen from water. The hydrogen would then be stored in tanks and fed into fuel cell to produce electricity as needed.

Initially, FireWater Fuel intends to develop an electrolyzer to produce hydrogen for energy storage at wind farms. It intends to create a commercial prototype of a freezer-size electrolyzer that would convert a few liters of water a day to electricity for consumers by 2015.

This still appears to be a work in progress.. here's what you can read on the Firewater Fuel Website;

http://www.fwfuel.com/opportunity.html

  We have developed state-of-the-art technologies and are in the process of deploying at scale.

For me, I am hoping to buy a turnkey system based on Ni-Fe batteries that is a slightly customized version of this package within the next month or two;

https://ironedison.com/freedom-package-24-volt-300-ah

There's no question that, if you are a tinkerer and want to dedicate a lot of your resources to such an endeavor, that you could make your own Hydrogen and do the fuel cell thing... for me alt. energy is just one thing on a long list and I don't have time to break new ground.. I just need and want stuff that is going to work when the going gets tough.      

silvervarg's picture
silvervarg
Status: Bronze Member (Offline)
Joined: Mar 28 2010
Posts: 57
Hydrogen vs batteries vs other options

Lets start with the freedom package.
It seems to be quite a lot of stuff, and without serious calculating I can't really tell if it is a good deal or not.
What does strike me as odd is that they sell a 2kW solar panel package with a single 300Ah battery.
With that much solar panels you would expect to have a much larger battery bank.
I guess the reason is that shipping will become a major price-issue if you have a large battery bank.
At least consider what size of battery bank you will need and what that bank will cost.

In general Ni-Fe batteries are quite expensive but lasts a lot longer that regular deep-cycle lead-acid batteries.
But compared to Litium polymer batteries that Tesla uses Ni-Fe is cheaper.

Have you compared the cost of Teslas package to the Freedom package?

Now over to the fuelcell part.
Converting anything to electricity is usually a quite inefficient process, so in the case of solar PV power we tend to store in batteries. The main downside is that batteries are bulky, heavy and costly.
So, if you want to put them in a car you tend to want the lighter and smaller LiPo batteries despite the high cost.
Still you don't get the same range as you get with regular liquid fuels.
One option is to use an compressed gas. Hydrogen is an option, but it is quite costly, so it is not used much commercially today. Natural gas is much cheaper and is used quite a bit on a commercial scale.
However we have still not seen a fuelcell that is fairly efficient , lasts a long time (15+ years) and has a reasonable price.
Todays solutions burn the natural gas in a ordinary engine.

One problem with compressed gas is that to fit enough gas you need really high pressure and the fuel pumps are really expensive, so they are not common as ordinary fuel pumps.
If you would break the tank or the fuel line in an accident with a compressed gas car it could get really nasty.

One other interesting option is to use a fuel cell that goes from methanol (liquid) to electricity. In ways of efficiency it will at best be about equal to a hydrogen fuel cell. The advantage is:
Cheap to produce.
Ordinary cheap fuel pumps can be used.
Easy to store in car (as it is a liquid).
Can fit enough in a car to go a long distance.

So, while it isn't perfect in every way, it could become a wide spread economical solution.
I should also say that with today's really low oil prices none of the alternatives can make a major breakthrough.
If you believe in oil shortage (say 5 years from now) and an oil price above $200/barrel then alternative fuels will start to push through the commercial market.

Michael_Rudmin's picture
Michael_Rudmin
Status: Platinum Member (Offline)
Joined: Jun 25 2014
Posts: 772
Compressed hydrogen

Compressed hydrogen is quite hazardous, because of sudden release. However, one of the ways you can store hydrogen at the density of several atmospheres is to embed it in titanium. Heat the titanium, and the hydrogen comes out: thus, your fuel cell.

The problem with titanium is that first, it degrades (hydrogen embrittlement) and the powder could damage your system.

So ideally, you'd like to store all those hydrogens on something that could simply be burned along with the hydrogen.

Therefore, another option is long chains of carbon. To get good reactivity, you do need a lot of branching on the chains.

We call those chains "high octane gasoline".

kd6iwd@gmail.com's picture
Status: Bronze Member (Offline)
Joined: Nov 17 2011
Posts: 25
inexpensive batteries

About 20 years ago I bought 2 banks of industrial nicad batteries from the Montrose Power plant in Colorado for $180.00. One battery bank had 180 amp hour cells and the other had 240 amp hour 1.2 volt cells in a battery bank of 128 volts total (106 cells per bank)The new price per cell at that time was around $300 dollars per cell. These cells were wet and had an electrolyte filler cap on each cell. The short circuit current through the cells was about 1,500 amperes and they all had dual bus bars. These batteries were in like new condition and according to the power plant had been cycled less than 20 times. They were buying new ones because they had a lot of money left over in their fiscal year and were spending it to forestall any decrease in their budget for the next year. These type of cells show up on the government surplus sales and if you bid slightly more than the scrap price of the cells you win the bid. Calling the agency that scrapped the cells can put you in contact with the person who was maintaining the cells prior to the sale and they will likely know the condition of the battery.

 

Jim

silvervarg's picture
silvervarg
Status: Bronze Member (Offline)
Joined: Mar 28 2010
Posts: 57
How to store hydrogen

Methanol is likely the most efficient way to store hydrogen atoms. The chemical formula of methanol is CH4O or more chemically correct CH3OH as one of the hydrogen atoms is connected to the oxygen.

The formula when you burn methanol is:
2 CH3OH + 3 O2 → 2 CO2 + 4 H2O

But running it through a methanol fuel cell is a more efficient way to get electricity.
You could theoretically create the electricity from the fuel cell as you need it, but in practice you want to have some kind of buffer. A battery is of course a great buffer (but you loose some efficiency). A super capacitor could be an alternative as you don't need to store that much energy and you hardly loose any energy when you charge and discharge a super capacitor.

We should just make sure that we don't boil the methanol, and that happens at 64.96° C (148.93° F).

Compare this to the boiling of ethanol (part of normal gasoline) 78.4° C.

So we need to be slighly more careful with temperature.
It might not be an ideal fuel if you live in hot deserts, but almost anywhere else it should work fine.

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