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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.
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.
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.
Here's some links:
Our team - Sunsetters
American Solar Challenge - ASC
Formula Sun - formula sun
The other teams - teams
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.
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.
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)