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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.
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).
to waste as fuel.
putting the 'B' in LGBTQ+
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.
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.