Nanowire Forests Use Sunlight To Split Water 56
An anonymous reader sends this excerpt from IEEE Spectrum's Nanoclast blog:
"One of the fundamental problems with fuel cells has been the cost of producing hydrogen. While hydrogen is, of course, the most abundant element, it attaches itself to other elements like nitrogen or fluorine, and perhaps most ubiquitously to oxygen to create the water molecule. ... Now researchers at University of California, San Diego have developed a quite different approach to mimicking photosynthesis for splitting water molecules by using a 3D branched nanowire array that looks like a forest of trees. ... The nanowire forest [uses] the process of photoelectrochemical water-splitting to produce hydrogen gas. The method used by the researchers, which was published in the journal Nanoscale (abstract), found that the forest structure of the nanowires, which has a massive amount of surface area, not only captured more light than flat planar designs, but also produced more hydrogen gas."
A simple answer means no attempt at a clue (Score:4, Insightful)
To sum up, the EROI (energy return on investment) argument is recycled from weird US anti-solar propaganda from the 1970s which lost all credibility when silicon based integrated circuits were mass produced and photovoltaics got the benefit of the being produced out of the same wafers. I'm assuming the hope is that a younger generation will not see it as the lazy bullshit that it is and swallow the lie whole. Did you swallow the lie or do you know it is a lie but are maliciously spreading it to cheer for your political team?
Also scammers will take anything handy to use as a tool to make money. Just because there are opportunists gouging people under the excuse of "green energy" does not mean that their tool is inherently bad.
Wind is crap at baseload but that doesn't always matter for several reasons:
Everything that is good at baseload has to be built at huge scales anyway, so building something small that is more expensive per MW can be a good idea if you don't need a lot of new capacity right away.
Covering the peak loads is often the big problem on a grid and small power sources that can be switched in quickly can solve that.
The small unit size means lower consequences of failure and makes scheduling downtime for maintainance easier, which is just as well because wind needs a lot of maintainance.
You don't want all your energy eggs in one basket. In a drought your inland coal, oil or nuclear plants can run short on cooling water for instance. The amount of cooling water thermal power stations need is staggering, but of course usually just comes out as warmed up water not a big deal unless there isn't much coming in from upstream or a dam is drying up.
Anyway, I'm not sure why wind has come up at all since it's about as offtopic as nuclear, which seems to get thrown up the second somebody mentions anything at all about energy. Getting back onto the point, there's no reason to limit this down to just writing about burning the stuff - it takes a vast amount of equipment to get hydrogen out of gas that is already conveniently methane/butane/etc on an industrial scale and there is a lot you can do with it. The majority of fertiliser is made from natural gas simply because that's the easiest way to get hydrogen to make ammonia. That's just one example. Hydrogen is very useful stuff in it's own right before you even think about burning it. A new way to produce hydrogen without expending a lot of energy that can be used without requiring equipment that fills a large space has a lot of potential uses.
Re:Hmmm... ZnO band gap is 3.37 eV (Score:5, Insightful)
Look at the carbon fixing (CO2-transforming) enzyme in nature: Rubisco. The elegance of the photon capturing and energy transport systems around it, and the machinery required to assemble the enzyme itself, will make you weep in amazement that it ever could have happened. The slow throughput of the system (molecules per second) and its bungling propensity to run backwards and re-oxidize (respiration), will make you weep in frustration.
Some plants (the C4 plants, such as maize/corn, sugar cane, and sorghum, typically evolved in hotter climates) cheat this up some by structural improvements that increase the concentration of CO2 through an intermediate structure.
We very likely have a lot of hard but interesting work to do, before we can design something comparable or better for human purposes.
Re:Efficiency? (Score:4, Insightful)
Why not use the wind energy to make hydrogen, and store the hydrogen (as a gas, as a liquid, or in metal hydrides)?
http://en.wikipedia.org/wiki/Hydrogen_storage [wikipedia.org]
Or why not use the wind to make compressed air, and store the compressed air?
http://en.wikipedia.org/wiki/Compressed_air_energy_storage [wikipedia.org]
http://en.wikipedia.org/wiki/Fuel_cell [wikipedia.org]
http://en.wikipedia.org/wiki/Hydrogen_economy [wikipedia.org]
Or why not use the wind to charge batteries?
http://arpa-e.energy.gov/ProgramsProjects/GRIDS/ARobustandInexpensiveIronAirRechargeableBat.aspx [energy.gov]
Or why not use the wind to heat up molten salts, and use a steam turbine to make power? Solar does it, but so could wind:
http://grist.org/solar-power/2011-07-05-groundbreaking-solar-plant-in-spain-generates-24-hours-of-power/ [grist.org]
Or why not use the wind energy to produce liquid synthetic fuels from carbon from the air?
http://www.staxera.de/announcement.105+M5320325207d.0.html?&L=1 [staxera.de]
Or why not use the wind energy to run energy-intensive industrial processes that can run intermittently (like grinding up rocks for fertilizer or chilling nitrogen out of the air)? And so on.
http://www.remineralize.org/ [remineralize.org]
There are solutions for the lack of buffers for renewable energy. Put them all together, and you have a way to use wind.
That said, LENR and cheap solar panels seem more likely to succeed, one because it is compact (if it really works) and the other because it has now moving parts and requires little maintenance.
http://hardware.slashdot.org/story/12/01/15/0226219/can-nasa-warm-cold-fusion [slashdot.org]
http://cleantechnica.com/2011/05/29/ge-solar-power-cheaper-than-fossil-fuels-in-5-years/ [cleantechnica.com]
"A Road Not Taken: Solar Panels, Jimmy Carter, and Missed Opportunities for Change "
http://www.renewableenergyworld.com/rea/blog/post/2010/06/a-road-not-taken-solar-panels-jimmy-carter-and-missed-opportunities-for-change [renewableenergyworld.com]
http://www.renewableenergyworld.com/rea/blog/post/2010/09/obama-no-thanks-to-carter-solar-panels [renewableenergyworld.com]
The true cost of fossil fuels:
http://www.treehugger.com/energy-policy/true-cost-fossil-fuels.html [treehugger.com]
"For decades now, fossil fuel company executives and D.C. politicians have worked together to ensure that coal and oil prices stay low enough to keep the American people hooked. In his new book Greedy Bastards, Dylan Ratigan explains how "vampire industries" like oil and coal have forged "an unholy alliance with government based not just on the money that they contribute to political campaigns and spend on lobbying but on their ability to hypnotize us with false prices." Industry gets tax breaks, subsidies, military support in volatile regions, the right to use our air and water like a sewer, and assurance that the government will clean up its environmental messes. Politicians get campaign contributions, a steady flow of dirty energy, and a talking point to brandish about how they kept gas affordable. But the Ame