Researchers find method to store solar power

[Judi Lynn]

Source: McClatchy News

Researchers find method to store solar power

By JAY PRICE

The News & Observer (Raleigh, N.C.) January 15, 2014

CHAPEL HILL, N.C — CHAPEL HILL, N.C. - A team of North Carolina researchers has discovered a potential solution to one of the fundamental problems of generating large amounts of energy from the sun's rays: how to store some of the power so it's available at night.

The scientists found a new way to use solar energy to split molecules of water into its atomic-level components: oxygen and hydrogen. The hydrogen can then be burned for fuel, generating only water as waste, which can then be recycled to be split again.

The hydrogen could be created and used by infrastructure similar to generators and solar arrays that are already familiar, said Tom Meyer, who led the research and is director of the federally funded Energy Frontier Research Center at the University of North Carolina-Chapel Hill.

"Part of a solar array, instead of just making electricity during the day, could in fact be making chemicals," he said. "So when the sun goes down, you just run the chemicals through your power plant, and you extract the energy back out as you need it."




Read more: http://www.mcclatchydc.com/2014/01/15/214616/researchers-find-method-to-store.html#storylink=cpy

[hobbit709]

1. What's new about that? We did this in high school back in the 60s.

[RobertEarl]

5. You used solar?

That would be amazing!! And you let it slip away? You forgot about doing so?

This is new, and it will replace coal and gas and uranium extracting companies. So they will be doing everything they can to say it doesn't work.

[jeff47]

9. This isn't new.

http://en.wikipedia.org/wiki/Electrolysis_of_water

Jan Rudolph Deiman and Adriaan Paets van Troostwijk used in 1789 an electrostatic machine to produce electricity which was discharged on gold electrodes in a Leyden jar with water. In 1800 Alessandro Volta invented the voltaic pile, and a few weeks later William Nicholson and Anthony Carlisle used it for the electrolysis of water. When Zénobe Gramme invented the Gramme machine in 1869 electrolysis of water became a cheap method for the production of hydrogen. A method of industrial synthesis of hydrogen and oxygen through electrolysis was developed by Dmitry Lachinov in 1888.

Here's an article on using solar panels to electrolyze water from Home Power magazine from 1994:
http://www.dangerouslaboratories.org/h2homesystem.pdf

[DLnyc]

11. Yes, but the article says they use sunlight directly to split the water molecules

You seem to be referring to electrolysis, where electricity is used to split the molecules.

[jeff47]

13. Nope, this is just a different way to do electrolysis.

They moved the electrolysis rig into a panel.

Doesn't really get you anything compared to just using the electricity. Especially with the pathetically low efficiency of this process compared to a "traditional" electrolysis rig.

[hobbit709]

10. Electricity does the work

difference is that now their using the power from the solar panels directly instead of a battery or DC supply

[djean111]

2. Oh, how lovely to think we could someday not be tied to The Grid.

[hunter]

19. Walk out to your main circuit breaker and turn it off.

(Or don't pay your electric bill for a month or two.)

It's really not that difficult "not be tied to The Grid." It's like quitting cigarettes or something.

My problem has always been that when I cut my electric power use to a level that I could afford to replace with solar, then the amount I'm paying for grid electricity is so negligible that solar doesn't seem to be worth the bother or expense.

It's either that or maybe that "living off the grid" is incompatible with my marriage. Living on my own I never figured I needed a refrigerator, washing machine, or clothes dryer. (My clothes didn't always smell so fresh either...)

But I'll be honest with myself, grid electricity is just too easy and too cheap. There's nobody stopping me from dropping off the grid. As the alcoholic says, "I can quit anytime I like."

But the larger part of the energy-environment problem is the fossil fuels we use flying and driving around, the fossil fuels we use making stuff to sell, the fossil fuels we use transporting that stuff around, and the fossil fuels we use heating and cooling the places that sell stuff.

If I simply don't buy most stuff, and I don't drive, then I'm using less fossil fuels than I would if I lived my life as an ordinary American consumer with a few thousand dollars worth of solar cells covering my roof.

[djean111]

20. Yes, I know I can turn off my electricity.

What I meant was - it would be nice if my power did not go out because something broke at the power plant.
It would be nice to know that I was not connected to a grid that could be shut down accidentally, by terrorists, by a car crash, whatever. It would be nice to know that access to the grid would not be more costly because fossil and nuclear fuel must always generate more and more profits at the expense of other technologies that are kinder to the earth.
I live in Florida. The grid is useless, sometimes, during and after storms. And the power companies run the show as far as costs go. They write the legislation.
Also am uneasy that all communications could be shut down merely by sabotaging the grid.
Stuff like that. It is not just about money. It is about the earth, and also about having electricity without being tied to the grid.

[hunter]

22. Then do it.

My life doesn't change much at all when the power goes out. If the water goes out yes. Maybe I'm being naive, but I'm trusting the local water company is properly maintaining their big diesel backup generators. Even so, I have water stored. I've also got enough solar panels to recharge my cellphone, my laptop, my radios... whichever communication systems are working.

It helps I live a mild California climate where heat and cold are not a threat to life. I like to believe I'm ready for the next big earthquake. My grandma lived in a place with a harsh winter climate. Her house had no plumbing so she never had to worry about the pipes freezing. Her winter comfort depended on the wood stove in the kitchen. Life without electricity would be easier for me than that.

[AdHocSolver]

24. Your post brought to mind a truth about our economic system that few consider these days.

The truth is that at some point of economic growth and interconnectedness, economies of scale become DIS-economies of scale.

That is, as organizations (businesses, companies, governments) grow, the efficiency of operation and cost to the user decreases, until a point is reached in which further growth and concentration of resources starts to decrease the efficiency and increase the costs.

Using the "power grid" as an example, to maintain a large interconnected group of power stations and users, necessitates operating huge generating systems running 24/7, plus a huge bureaucracy, and the transport of huge amounts of fuel from source to centralized generating systems, while at the same time leaving the entire system vulnerable to a widespread collapse of the entire system from a cause that would be a minor inconvenience to a small part of the system if the users were in smaller, separated networks.

If manufactured goods were produced locally in areas where they were to be sold rather than in giant sweatshops thousands of miles away and shipped at great cost to the purchasers and the environment, not only would this create more jobs locally, but the goods would be much less costly to purchase.

I read recently that a company that raises chickens in the U.S. plans to ship the chickens to China for processing and then ship them back to the U.S. for sale. That chicken grower must be owned by an oil company or a shipping company. While it may be good for corporate profits, how would it benefit the consumer who will have to pay for shipping costs both ways?

[fasttense]

25. Our biggest export is agricultural products AND

Our biggest import is agricultural products. In many cases, the exact same item is exported AND imported.

As you noted, these built in inefficiencies of capitalism and corporations are never questioned.

[silverweb]

3. Duh.

[font color="navy" face="Verdana"]There's a guy in NJ who's been doing this for years. There was a big writeup about him in some publication a few years ago. I figured it was simple, brilliant, and would be a pretty widespread practice by now, but this article makes it sound like reinvention of the wheel.

[Warpy]

4. Well, duh. A pilot program for closed systems

has been up and running for years, a solar powered house with excess power fueling electrolysis, the oxygen and hydrogen being used in a fuel cell to power the house at night.

[DLnyc]

16. Again, using sunlight to split water is not the same as using electrolysis.

If your solar panels convert about 20% of the available sunlight energy to electricity, and then your electrolysis process is 50% efficient, and then your process of converting the hydrogen back to electricity is 50% efficient, you are ending up with only about 5% of the available energy.

Eliminating a step (using sunlight directly to produce hydrogen) could be an important advance, depending on the efficiency of the process, both in terms of available energy and in terms of cost (dollars) per watt-hr.

[longship]

6. Kind of an obvious solution about which has been known for years.

[libdem4life]

7. It will be utilized when, and only when, the PTB are ready or able to make a profit.

[loudsue]

15. Bingo! If they can use it to SUCK the money out of the American people,

THEN and only then will it be available to all.

[JDPriestly]

18. Absolutely correct.

[yellowcanine]

8. Researchers discovered batteries????

Huh. Imagine that.

[Igel]

12. No.

The problem with storing solar energy is simple.

Batteries are big, expensive, and inefficient. Then, when they're worn out, you have a toxic mess to recycle and a lot of chemicals to dispose of. Bad.

Other ways of storing the energy are idiosyncratic--using the energy to pump water uphill, to pressurize gas. Then the potential energy can be converted (inefficiently) using turbines of some sort. Less polluting, but still wasteful.

This uses what amounts to the first part of photosynthesis. There was another breakthrough last year concerning this, but it was in a system that still had some drawbacks. This removes at least one of them.

Photosynthesis is pretty efficient.

The result is hydrogren, which can be used in fuel cells to produce electricity in a fairly efficient manner. Properly stored, the hydrogen is safe. Moreover, it can be transported (although that's a bit riskier). And there's no reason that you couldn't vastly overproduce the hydrogren for periods when the day was short or overcast.

[kristopher]

17. That view is out of date...

Batteries are big, expensive, and inefficient. Then, when they're worn out, you have a toxic mess to recycle and a lot of chemicals to dispose of. Bad.

Lithium isn't big, I can buy it now for about $150/kWh, large scale buyers are down to about $100/kWh, they are not a "toxic mess" to recycle or otherwise and the are not bad. They also demonstrate extremely high levels of round trip efficiency - especially in comparison to photosynthesis.

Storage and transport of H2 is Extremely difficult.

Over production for storage is a given, but the technologies that are out there are pulling us away from hydrogen.

[hunter]

21. Pumped hydro is about as efficient as you get. Photosynthesis is not.

Except for the area under a forest canopy, plant growth is rarely limited by the amount of energy available from the sun. In fact living plants shed a great deal of excess solar energy.

For now plants have one great advantage over any artificial means of photosynthesis because plants manufacture themselves.

If we quit extracting fossil fuels tomorrow we could make many of the things we need from plant materials.

[kristopher]

14. It's legitimate basic research, but not a breakthrough

It's claim to fame is that it reproduces photosynthesis with a process that looks capable of raising the efficiency to 15X what a plant could do.
They use direct sunlight to power the reaction, not electricity, so the process commences with the input of solar energy into the medium that delivers the captured energy as pure hydrogen - which is a different, sometimes more useful output than plant sugars.

The only criticism I'd offer is that the press release reinforces the meme that storage is a much larger problem than it actually is. There are a large array of technologies and approaches for dealing with variable sources of generation that we will be integrating into a distributed renewable energy system; this might well be one of them but there is no Holy Grail of storage required.

[rickford66]

23. the same method should be used in existing power plants

I've been saying for years that the excess power that is always on line for fluctuations could be used to produce hydrogen. Of course the hydrogen generation would stop as soon as there's more demand than available.

[Stuart G]

26. k and r, no text..