Breakthrough in solar efficiency by UNSW team
smh.com.au
smh.com.au
This finding is technically neat, but I don't see how it is a breakthrough by any means. Admittedly, I only read TFA.
The article is definitely more hype than substance.
Did you ignore the part of TFA that was about cost reduction?
Silicon wafers account for more than half the cost of making a solar cell. "By using lower-quality silicon, you can drastically reduce that cost," he said.
Although there is no shortage of rooftop space, you could still fit them into places where there currently isn't so much space. Perhaps, at some point, we could put them on top of electric cars, making them less dependent on charging sockets.
There's plenty of solar capacity on the planet to meet not only present electric generation demand, but the growth require for substituting much present fossil-fuel usage with electricity. Probably even bringing up per-capita energy allotments to a reasonable fraction of Western levels (1.5 - 2.5 kWh/day would make a huge difference for most people's lives).
The real challenges are cost -- building out solar capacity would require 8-9 doublings of existing capacity, at least. Financing this (or ramming through the construction regardless) is going to be the biggest challenge.
Storage though is the other bogeyman. There's very little pumped storage available. Grid batteries, likely emphasizing cost over size, weight, or efficiency, as there simply isn't enough of many common battery materials to meet requirements, thermal storage. Maybe hydrogen production, maybe electrically-powered synfuel production, flywheels.
There are a few reactor options, mostly still not commercially proven, which may help bridge the gap: TerraPower, LFTR, and other breeder designs. Relying strictly on conventional uranium fission reactors would burn through known reserves in a few decades -- 30-80 years.
Germany is exploring the possibility of converting excess electricity to gas: https://en.wikipedia.org/wiki/Power_to_gas
It would be really interesting to see numbers on the maximum amount of excess power that could be stored if those two techniques was universal utilized for this purpose.
Direct thermal storage addresses some needs but not actually providing grid-level storage.
Thermal electric storage does seem based on reading and some back-of-the-envelope calculations to be one option that scales reasonably well. It can be based on cheap, abundant substrates, and fits well with existing technology for converting between electricity and heat (or for CSP where heat is banked during the day).
Tom Murphy's "Nation Sized Battery" presents some good numbers. If you want to extend his coverage to other techologies, you're going to want their storage density (by volume or kg), round-trip efficiency, and materials cost and availability. The key to me is that you need massively abundant, massively cheap materials. http://physics.ucsd.edu/do-the-math/2011/08/nation-sized-bat...
While strictly speaking true, this is completely irrelevant. "Known reserves" refers to the surveyed amount that is technically and economically feasible to extract at present market prices. The cost of uranium ore is a vanishingly small part of running a nuclear plant -- fuel costs are less than 10%, and the vast majority of that is enrichment and processing. Uranium market prices could go up by two orders of magnitude without endangering the industry, and at that point, we have milennia of known reserves (mostly in seawater).
I haven't looked extensively at the fission fuel issue, but that estimate is one that's fairly widely disseminated, including by the nuclear power industry. I see values from 5.4 - 6.3 megatons of uranium.
The problems are that:
1. Existing scale of fission energy generation is a small fraction of a "total replacement" estimate.
2. Even if there are extensive amounts of uranium, recoverability and net EROEI matter. Unless the extraction process is tremendously complex, nuclear chemistry should tend to make this favorable, though it may still be expensive in terms of time, plant, technology, and/or other limiting inputs.
3. This calls for betting the farm on unproven technolgies or reserves. We do know that solar is sufficient for at least the next century or so. During which hopefully humanity can get its population back under control and to sustainable levels.
I'm aware of the concept of proven reserves. I'm also familiar with models of resource extraction and exhaustion such as Hubbert's work in oil, though not of the specifics as applicable to uranium. The IAEA's got some light reading on the topic: http://www-pub.iaea.org/books/iaeabooks/1357/Methods-for-the...
And as mention, breeder designs change the maths a bit.
Sources / math:
http://www.sjc.ox.ac.uk/3675/Energy%20Challenge.pdf.download
http://www.iaea.org/newscenter/pressreleases/2010/prn201009....
(And the math done here showing we'd exhaust those reserves building the first 5,000 of the 17,000 1GW plants required to meet present demand at a cost of $52 trillion: http://terrydyke.com/2011/06/even-if-nuclear-power-were-safe...)
http://terrydyke.com/2011/06/even-if-nuclear-power-were-safe...
2) EROEI is fantastically, ridiculously good for everything nuclear-related. Even the worst uranium mining schemes beat everything else by a million times. And the costs are still minimal even with the more exotic extraction schemes. There have been trials of them, they have been successful.
3) Solar is incapable of being used as baseline generation. All intermittent capacity needs to be backed by something else. Right now, that's gas turbines. Fracking will make this feasible for ~30 years, beyond that we need something else.
The Hubbert's work in oil is not really applicable to Uranium, simply because there are effectively unlimited reserves of it at an economically acceptable price points and fantastic EROEI levels.
Ignore all articles regarding solar breakthroughs unless:
1) they have a sticker price on their web site, for sale immediately 2) they don't need investments to get a business off the ground 3) they have links to all research and patents that capture what the breakthrough is all about.
Enough with the solar power hype machine. Give it a break. Show me something with a "buy now" button or go home.
Seriously, 20 or more articles in the last year? All with some incredible breakthrough? Enough already.
If you believed the commercial success of all the solar panel breakthroughs we have been hearing about, then by now every solar panel would be the size of a postage stamp, be generating 12 KW of power by moonlight and they would have been giving away a free solar panel with every six-pack of beer...
So while it may be annoying to read about the 10th PV technology breakthrough of the year, there is no doubt that these breakthroughs have a real effect on the price and efficiency of solar panels. I think it's interesting to read about this.
The most efficient commercial solar cells available today are (as far as I know) the Maxeon line and their rated efficiency is 24%, so even that claim holds no water.
What I find a bit annoying is that any news item that contains the words 'breakthrough, solar, efficiency' will automatically get wide distribution.
You can probably find one such announcement per month and it usually amounts to nothing once the dust has settled.
Are there any meaningful differences in the toxic byproducts of manufacturing, transport, and/or disposal of the panels?
I might care about that, too, but I've heard very little about it.
At present, the best commercial solar cells convert between
17 per cent and 19 per cent of the sun's energy into
electricity. UNSW's technique, patented this year, should
produce efficiencies of between 21 per cent and 23 per cent. The breakthrough involves using hydrogen atoms to counter defects in
silicon cells ... [so that] poor quality
silicon can be made to perform like high quality wafers.
But there's no reference to patents or to research demonstrating these claims, so I don't know what to think.
Funding to help commercialise the technology will total about $15 million over three years, with the UNSW seeking support from the federal government’s Australian Renewable Energy Agency for part of that sum.
Most of the time these articles are very vague about any real application.