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New Material for More Efficient Solar Cells
PunkerTFC writes "Space.com has an article on a new material that could create relatively cheap solar cells which are up to 50% efficient. This is much better than the 25% efficient silicon solar cells (most common) or the 36% efficient multi-junction solar cells (very expensive). The material was created by "forcing oxygen into a zinc-manganese-tellurium crystal" creating more band gaps, which allow the cell to create electrical energy with three seperate frequencies of light. This could lead to cheap, high-output solar cells in the future, but it will take at least 3 years to assess the feasibility of the new technology, according to the researchers."
It exists already.
This has been released very recently - it's based on PbSe crystals instead - at Los Alamos but also through University of California.
This was already covered by /. a few weeks ago, but this new space.com article does seems tohave more details.
I think he's talking about the American Solar Car Challenge. Its quite an interesting activity, especially all the different tricks the teams use to try to get more performance out of their cars. (And there's quite a variety!) I know one of the coders who was on Principia's team last year (they came in 4th, which is really impressive, considering some of the competition) and the stories about all the stuff they went through to get a working car are fascinating.
I can safely tell you to expect a huge advancement from the research labs (UCLA specifically) by the beginning of next year, January 2005. Expect MUCH more power per volume compared to our current lithium ion batteries, and my friends at the lab have reduced production costs by nearly 66%.
Expect an formal announcement of the January date sometime early this summer (I was told June or July).
Background: 28/M/Bi-Sexual; Owner of a Linux company; MBA Harvard 2003; B.S. Comp Sci MIT 2000
google
Tellurium is about $14/lb. Gallium, by comparison, is about $1000/lb, which is why gallium-arsenide photocells, which can reach 30% efficiency, aren't widely used.
World production of tellurium is only about 100 metric tons. Gold production is 25 times larger. Tellurium is cheap because it is produced as a byproduct of copper smelting. Nobody mines tellurium directly at present. So there may be a supply problem if demand increases substantially.
Hydro power is now on the way out as a major power source. Many dams have been removed in Western countries because they lead to salinization of cropland, destruction of hatcheries, and they just cost so bloody much. More dams have been destroyed than built in the last 20 years. On the other hand, wind and tidal power are becomming more viable because they do not munch the ecosystem in quite the same way. Besides, wind turbines will cool the atmosphere by some tiny amount to offset global warming.
1100 watts/m^2 * .23m * .3m = 76 watts
76 watts of solar power * .5 (50% efficiency the article mentions) = 38 watts of electrical power.
And that's if this research pans out and if the price becomes practical and if you aim it directly at the sun on a perfectly sunny day.
sorry to have correct you,
No it's not.
It's ~ 1kW/m^2 not 1kWh/m^2.
In order to get ~ 1kWh you need to have one hour of bright sunlight per square meter
Hope that explains it to you.
Make them cheap and light and send them in space
And wait decades for them to pay off the energy required to lift them to orbit, especially at microwave energy transmission losses . . . except the panels will be rendered inoperative by micrometeorites first.
Solar power satellites are only practical if you either have space manufacturing out of lunar/asteroid material, or a beanstalk.
From the Mineral Information Institute:
Uses
Half of the tellurium consumed each year is used to improve the machinability of special iron and steel products. It is alloyed with copper to make copper more ductile (that is, easier to stretch into wires), and with lead to prevent corrosion. These, and other nonferrous tellurium alloys, account for approximately 10% of tellurium use.
Tellurium is also used to make catalysts and chemicals. Some of these chemicals are used in the petroleum industry and in making rubber. Tellurium is added to selenium-based photoreceptors to broaden the spectral range of copiers. Tellurium is also used in other electronic applications, and in the production of blasting caps for explosives.
That was the turning point of my life--I went from negative zero to positive zero.
Here's some links:
Our team - Sunsetters
American Solar Challenge - ASC
Formula Sun - formula sun
The other teams - teams
Telluride is used also in other optoelectronic materials such as CdHgTe for IR detectors, and if there ever was a nasty material to work with this is it. I would not be surprised if this new one is bad too. In fact "forcing" oxygen atoms into this crystal has to distort the lattice making epitaxiality a nightmare.
So it might be nice and efficient once (or if) optimised) but also it might be horrifically expensive.
Seems to me like the best way to go is some sort of thick concrete wall structure that stays cool in the summer. Then use the latest in lighting technology [are white LEDs feasible for indoor use?] and generally minimize electronics within--find a high efficiency fridge, low power computer, etc. I think you could have made it work if you had planned the building from the ground up and made some lifestyle changes. Maybe line-dry clothes rather than with a machine, if it is feasible in your area.
Of course I'm speculating heavily.
Even this relatively pessimistic scenario would still be a big win for the environment: it's much easier to add anti-pollution technology to a few large coal plants than it is to get every single car-owner to upgrade their car. Plus, when renewable energy sources do finally become a cheaper way to produce hydrogen, it will then be a painless transition because most everything will already be hydrogen-compatible.
I don't care if it's 90,000 hectares. That lake was not my doing.
You could always electrolyze water and store the hydrogen and oxygen in tanks. The tanks of gas become your battery and a power cell can be used to generate electricity on demand.
I am not denying that this is possible, but it has to be acknowledged that now the main cost driver of your system is probably not in the solar cells but in this oxygen/ hydrogen separation, storage and electricity generation system. Which illustrates my main point which is that good solar cells are not by themselves sufficient to enable this form of a solution (although of course they are a great step).
Tor
Yes, of course. My point was, after all the cars are upgraded to run on hydrogen, then we are free to switch to any method of hydrogen production we like, as often as we like, without having to upgrade all the cars again each time.
Nice try, thanks for playing.
Don't be such an ass. Sometimes when things don't make sense, it's because you didn't understand the post, not because the post was wrong.
I don't care if it's 90,000 hectares. That lake was not my doing.
let's hope these make it to market soon, and that they are cheap when they get here. this is a huge leap in efficiency, and if the price is right, it could be quite competitive with other forms of energy. this would reduce our dependence on foreign oil and could stimulate our semiconductor industry if production really took off.
they need to figure out a way to make solar cells in more complex shapes. It even with current solar cells, the efficiency is great enough to make a decent commuter car, so long as it's covered with cells. It's not like it won't be spending most of the day in a parking lot somewhere. But a car covered with PV cells can be pretty ugly- if high efficiency PV's could be formed into body panels, particularly if combined with something like BP Solar's Laser Grooved Buried Grid (LGBG) process which hides the bus bars and allows for different colors, a normal-looking solar-powered car could be possible.
Once used, nuclear waste needs to be stored. this waste has a half life of thousands of years, and it needs to be put in a place where it cannot harm anyone or anything for this period of time.
Actually, read up on breeder and CANDU reactors. (As a concrete example, Argonne National Laboratory ran the EBR-I/EBR-II/AFR project, a testbed for a passively safe breeder reactor design -- see this sidebar about "burning" nuclear waste and this article about next-gen reactors. I can't squeeze from their site whether or not they ever built the AFR itself, so I'm assuming not.) The reason the waste of traditional fission reactors is radioactive for so long is that everyone's paranoid about recycling it, because it might conceivably be used by technicians at the plant to make plutonium. If the waste byproducts were recycled into breeder reactors, the medium-term byproducts (those with multi-1,000 year halflives) could be broken down into a mix of more stable atoms plus some short-lived (100-ish year HL) waste, which is a lot more reasonable to deal with. Basically, if it's noticeably radioactive, it's better to release that energy in a usable form right now rather than let it sit around leaking that energy into the surroundings for millennia.
Range Voting: preference intensity matters
Home Power magazine used to be the place to learn all you needed to know about everything solar & alternate energy related. Now that you have to register to download the huge PDF, I'd say just surf the newsgroups and blogs.
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Fuel Cell technology is great if you want to run your house off natural gas, propane, whatever. Unfortunately the price has gone sky high because california sucked up every cubic meter they could so THEY could have clean electric power. Now its no longer a cheap way to heat your house. Might as well go back to electric and choke down that coal plant radon/throium ash leakage.
But anyway, batteries, even though they contain evil awefull lead, are basicly fuel cells and hydrogen storage in one. You charge em, they generate hydrogen ions, and burn em when they discharge. Maintaining them, and knowing when your charging module is starting to buy it, or you have a bad cell, or a bad solder/connection on the bank is a black art in itself. But well worth it once you get all the details down.
Knowing what you absolutely need to have for non generating hours reserves if you get bumped off the grid, learning to get all your high wattage tasks done at peak generating hours is all part of being mostly off the grid.
If your going to cough up the bucks, I'd recomend getting the CD archives of homepower magazine. They're about $10 per (5-6 issues per CD), and less for the whole collection. Lots of diagrams, case studies for power systems. Dirt cheap compared to the cost of your first replacement inverter(also a regular replacement item)
As an end note, lead cells are cleanly recycled when you dump em off at the right places. The problems come along when you chuck thin walled car batteries into the local landfill to join all the dead Ni-Cads(really toxic to people) and old metal junk. CRT glass by itself is relatively safe and inert, but makes more sense to recycle.
Lead is not so bad as toxic waste is concerned, but you typically can use up a whole lot real fast and it piles up if not recycled. And being a slow reacting metal, it'll seep into groundwater for eons. Thinks like manganese run off the fields, into the groundwater, and you get a whole lot of younger people with parkinsons 10-20 years later. Cadmium is somewhere between the two for nasty side effects and reactivity.
Forget nuclear war for making mutant babies, dead cell phones batteries in the landfill will do that just fine. (doctor evil laugh here)
You're not clear on whether or not you're counting state and federal rebates on your PV costs. In California we've got this program which provides serious cash for people interested in installing their own renewable energy (RE) system. If you don't live somewhere with such a rebate program you might try writing to your state representatives and ask them why.
Also, your brand new PV system will likely last at least 25 years, possibly much more. Such a system can also add quite a bit of value to your house. After 15 years your PV panels will be doing nothing but saving you money and raising the value of your house. On a 30 year scale the PV system will make you about as much as if you had invested it, possibly more if you can get tax credits and/or rebates. You're also likely to make some money on the PV system when you sell your house since it is a 'utility' upgrade more than a stylistic one.
I'm a loner Dottie, a Rebel.
Rocking horses are made of wood. That makes Rocking Horse shit fairly unusual.
Government of the people, by corporate executives, for corporate profits.
From what I've heard, in California, the state will pay for close to 50% of the total cost of the system . And, your electric company doesn't pay you for your daytime electricity, your meter runs backwards when you generate more than you use. This is called Net Metering and is the simpiliest way to do it as long as you just want to take care of your own energy needs.
The part you mentioned about them paying you for your excess is probably related to what's called Time Of Use ( TOU ) metering. With TOU metering, you pay(per month) for an extra phoneline hookup so the power company can read your meter every 15 minutes. Then they'll read you meter and determine how much the power costs at that time and how much you generated and then pay you accordingly. Net Metering is the easiest and there's only a yearly bill with monthly statements. If you size your system correctly, you'll only pay about $100/yr for all the federal and state taxes that are tacked on to everyones monthly bill.
Like many other states, California is promoting alternate energy systems and helps pay for some of the system costs. Search the web and I'm sure you'll find out what's available in your area.
BTW, we are 100% solar powered.
LoB
"Anyone who stands out in the middle of a road looks like roadkill to me." --Linus
There is a very clear online recent lecture on this topic by Nathan Lewis, a chem professor at Caltech who is active in this field. It is titled "The Future of Power and Energy in the World" You an find it with many slides at http://online.itp.ucsb.edu/online/colloq/lewis1/ The summary is roughly that we need to make photovoltaics about 10 fold cheaper than they are today(about $4/watt ->$.40/watt), on the way to making them as as cheap as housepaint. There is no theoretical obstacle to doing this, and several promising lines of research. If (really when) we can do this ($.40/watt), solar electric energy will be cheap enough to electrolytically reduce CO2 to methanol (CH3OH) which is a fine fuel for transportation, etc., and is already nicely interfaced to out current energy distribution and use systems. At this low cost, we can even pull CO2 out of the atmosphere directly, directly reversing the CO2 greenhouse effect. Furthermore, this is by far the best option, e.g. 5000 new fission reactors would be needed to supply the growth in energy needs contemplated in the next 50 years (construction of 2/wk for 50 yrs.) This seems much too dangerous. Since this is the best apparent practical way out, since we are really talking about a major determinant of the fate of the earth, and timing is critical, one might wonder why the funding is so low (about $10M/yr in the US maybe).
>Of course, we all know the electric companies are going to call this "stealing energy" and patent the sun...
s /2 003.04/20030408-3.html
Sadly, something akin to this almost happened! California didn't want companies skipping out on the state's $6B energy deficit, and proposed what amounted to a tax on use of solar energy:
http://www.californiasolarcenter.org/solareclip
(Thanks to a major public and corporate outcry, they backed off.)
This was rather ironic, given that CA had been subsidizing as much as 50% of the cost of photovoltaic installations. Along with CA's high sun exposure, this makes it one of the few places where solar power is truly cost-effective.
I do hope that advances like in the parent article can bring the cost down someday. But even then, the biggest part of the solution to our energy woes will be the same as it is now: CONSERVATION. There are many simple, un-glamorous things you can do NOW to cut enery usage in half or less, such as switching to compact flourescent light bulbs, and unplugging all those wall warts, er, AC adapters when the devices aren't being used.
It's even theoretically possible to turn off your computer sometimes. (And use a switched power strip if you do -- even when a PC is off, it's still using some power for 'standby' mode, waiting for Wake-on-LAN or something else to turn it back on.)
In general, every $1 you spend on conservation efforts is worth about $4 in renewable energy production.
Just about anything you might want to know about alternative power systems can be found here: http://www.homepower.com
Regards,
=bitrot=