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Innovative Use of Plastics Could Cheaply Double Solar Cell Output
doug141 writes "In standard solar cells, much energy is lost (as heat) from photons mismatched to the capability of silicon to capture them. A new technique uses a pentacene layer to down-convert each hot (un-captureable) electron to two electrons that can be captured by standard silicon cells." You can read more at the University of Texas research group's web page.
It would be really interesting to see what happened if solar energy became affordable enough to power people's homes. Based on current technology, the cost of solar panels is several thousands of dollars for a typical home's electricity needs. Over the lifetime of the panels, that's about 30 cents per kilowatt hour, which is three times the cost of typical utility fees. I wonder if there would be resistance from power companies if people were able to put cheap solar panels on their houses, or if they would buy up all the patents so you had to buy your panels from them.
Slashdot seems to post a lot of stories about improved solar cells, but solar cells never seem to improve.
from http://en.wikipedia.org/wiki/Pentacene
It turns out that Pentacene breaks down on exposure to air and light.
Which means that more reasearch in this direction will be needed in order to have a practical use for this discovery.
The economy is going to force us to change our lifestyles in more drastic ways soon enough.
Solar panels have fallen significantly in price. Instead of being laughably expensive for electricity, they are now just pretty expensive. The need of structures to hold solar panels, power electronics and wiring remains unchanged.
Will they cost twice as much?
Even if solar panels last 20 years, the technology seems to be improving every 6 months or so making the value drop at the rate computers do. Who knows where solar panel technology will be in 20 years. I wonder how many people are waiting on buying solar because every few months another story comes out about great improvements.
This effect has been known theoretically for quite a while, and experimentally for a few years at least. Look up the literature on "singlet fission" or "multiexciton generation." The process works by photon excitation to a singlet excited state, followed by the reversion of that excited state into 2 triplet excited states with roughly half the energy. Thus the extra energy that would normally be lost as heat can go into exciting another photoelectron. The neat thing about this paper is that, for the first time, the researchers were actually able to show a >100% photoelectron generation, meaning that they got more electrons out than photons that they put in. This is a huge vindication to this direction of research, which has recently been seeing quite a bit of skepticism as to its legitimacy (since not having greater than 100% photoelectron generation can be explained away by other possibly competing processes, but the result from Zhu's lab pretty much nukes those competing theories).
The battle for solar panels is not performance but entry cost
As written, the summary would be announcing the most spectacular physics discovery in a century. Charge conservation fails! Too bad it's not what was meant: s/electron/photon/ .
to waste as fuel.
putting the 'B' in LGBTQ+
Seriously, where will it be installed at? Will it be licensed to American companies (where we have paid for this R&D), or will it go to China?
I prefer the "u" in honour as it seems to be missing these days.
We use FIT and other means of subsidies to drive solar and wind, but ignore other solutions. However, in just about every single case, it is a retrofit, which is expensive. But, there is a simple solution for all of this.
America, or even states, could require that all new homes and buildings under 4 stories, have 50% or possibly 100% of their HVAC (heating and AC required) come from on-site AE. This would actually encourage several things:
1) a number of contractors will simply throw up solar panels equal to the amount.
2) a number of other contractors would heavily insulate and drop the energy needs to the point, where a MINIMAL amount of AE is needed.
3) a number would try something like geo-thermal HVAC combined with 2 to allow them to drop it to one panel.
Basically, by adding this requirement, it would change the NEW buildings and separate them from the old ones. Considering the number of foreclosures that we have now, the last thing that we really need are new buildings that compete with many of these foreclosed buildings. At the same time, it pushes various AE without loads of incentives, while allowing contractor to move to whatever direction is economical and will sell.
I prefer the "u" in honour as it seems to be missing these days.
The problem is "some changes". Which is somewhere between replacing all devices on the electrical network to support full bidirectional transmission, and replacing every last piece of transmission infrastructure we have. Ignoring that in practice we probably need to build a whole lot more in the process. In order to reach the transmission efficiency that most "solar is cheaper" systems depend on we'd need HVDC lines everywhere (not just plant -> homes, but every single location would need high capacity east and west uplinks, so we can have follow the sun(/wind) transmission, additionally we'd need lots of south -> north capacity), and superconducting transmission within cities.
We're apparently talking between $800 billion up to several trillion dollars. Most electricity networks are broke, more than a few are bankrupt.
The alternative is battery systems in every home (would still be massively less efficient, but it might actually work). That does mean however installing 200kg of (toxic) batteries (at least) every 2-4 years or so. Of course, this is never going to work north of some point. Not just Alaska. This would also actually cost more than the nationwide infrastructure, but it doesn't need to be paid by the government.
Hell, even Obama would think twice before building "some changes", even with other people's money.
I'd still like to see all freeways lined on either side and in the middle with PV panels. Even better would be to put salt beds under to store the energy.
A fool throws a stone into a well and a thousand sages can not remove it.
http://news.cnet.com/8301-11128_3-57333084-54/military-deploys-distributed-solar-en-masse/?tag=mncol;posts
Is the way to go.
Don't be apathetic. Procrastinate!
Perhaps people are trying to reduce the price of the wrong thing.
Deleted
This is in fact the way it would go. Set aside the utopian fantasies and look at it from a normal business and consumer perspective. Business avoids the higher cost in materials, construction labor, etc. Consumer does what he wants/needs for as cheap as possible.
Result: Law to force utopian concept gets circumvented and the consumer, again, pays more for what he needs/wants.
Cue the revised utopian concept assuring laws.
The simple fact is it boils down to economics. When solar is cheaper(it isn't and close doesn't mean shit), solar will be chosen. Until then, every idea imagined to prematurely force solar, wind, whatever alternative energy du jour sucks!