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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."
Solar cell technology seems to be getting more and more advanced. When will the time come when we are able to use it to effectively power a complete house?
Now I can overclock my cheap solar-powered calculator!
This has been released very recently - it's based on PbSe crystals instead - at Los Alamos but also through University of California.
Solar panels could really be the next generation power-source, if it can be developed a cheap and efective way of using solar energy. Have you seen that short-film on Discovery Channel about the guy who built a car that runs on solar power alone? You can walk faster than it, but hey, you could walk faster than the first steam-locomotives as well. But i'd still say that hydro-plants are the way to go, if the terrain allows it.
this is probably the most boring sig in the world
It would be awesome to have a car that was able to "refuel" itself while it sat idle most of the time. Cars have so much surface area that is exposed to the sun, it just seems like this would be a great fit, although the sun obviously couldn't be the sole source of power.
Now I can use it to power my computer without having to pay electric bills!
Wait...what happens when it is cloudy?
Of course, we all know the electric companies are going to call this "stealing energy" and patent the sun...
...but until it progresses to the point where we don't need a surface of cells an order of magnitude larger than the structure they will power to use them, they're still impracticle for primary energy needs.
I don't think we'll ever see solar cells as primary terestrial energy sources though. Cloud cover and night ruins their feasibility, but I'd wager money on them being used to augment other alternative energy sources in the future. Maybe power will go the way of Intel's new chips, multiple sources at lower power instead of one giant one at greater.
...how's it going to help me use my calculator at night?
Oil reserves appear to be running out (looking at the recent problems Shell had with its overstated reserves, and seeing how some of the other large oil companies make even larger estimates than Shell's old ones). The future of energy production is going to be nuclear, wind, and solar. So it's very timely news.
Personally I think the collapse of the oil supply within the next 15-20 years will be the most traumatic event in recent human history.
Solar cells will help a lot in some ways but they won't be enough to stitch together a modern society built on the motor car and cheap fuel.
Sig for sale or rent. One previous user. Inquire within.
You have false notions about the feasability of solar. You would be speaking of cheap solar whereas (as it is now) there ISsolar technology that:
A) Doesn't have to cover the entire structure - but really is mute point - if you want solar - why not maximize its production - installation and deployment is 1/4 the cost - once it's being installed, install as much as possible - your goal is to "overproduce" if possible - did you know that your local energy untility has to BUY BACK power that you could place onto the grid if you overproduced?
B) The GM solar race car is a marvel of engineering, is as fast as most street legal cars and it looks cool too!
C) Cloud cover and night are of no consequence. Cloud cover only reduces production - besides power IS STORED in batteries anyway - it doesn't go straight from the sun to your light bulb or TV.
Yell & scream & rant & rave... it's no use... you need a shaaaave ~ Bugs Bunny
This was already covered by /. a few weeks ago, but this new space.com article does seems tohave more details.
Just after I invest $6K in a small solar plant to run the servers here...
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http://jsl.com/solar
The solar constant (see for example here is about 1.somethin kW per Square meter.
That simply means you need quite some substantial area irradiated by bright sunlight to obtain a given amount of energy.
I think this is a limiting factor for many interesting ideas out there..
perl -e 'printf("%x!\n",49153)'
One alternate plan is to use cheap titanium dioxide to make less efficient solar cells that are significantly less expensive. Titanium dioxide is used to tint paint white and is available cheaply in bulk. While researchers are working on increasing the efficiency through nano particle techniques, do it yourselfers have made progress.
but really is mute point
The point may be moot, but it is never "mute."
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
...to study technology feasibility. Hmmm. More like, 3 years to quietly let this technology get stuffed into the same warehouse along with the 60 mpg carburator and the Ark of the Covenant.
They say the first thing to go is your penis. Well, it's either that or your brain. I forget which...
-Matt
Solar sales are up 30-40% every year, and have been growing at such a steady pace for a long time.
Naturally, this is a positive feedback loop. Lower prices mean it's affordable for more niches, which means more people buy, which in turn scales larger. At this point, it's pretty much unstoppable. It is useful in too many niches, especially where customers aren't connected to a power grid.
There are now many countries that have more cell-phones than landline phones. It's likely that in 10 years, some countries will have more customers getting electricity from solar than from a central grid. Naysayers will say it's not ready... but then again, 15 years ago cell phones weren't either. What matters is not the absolute numbers, but the growth rate of the industry and the evolution of the technology.
Of course, as the market matures, more people are doing R&D to find cheaper ways to build PV systems, which is only going to accelerate this momentum.
Information: "I want to be anthropomorphized"
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.
50% efficiencies are quite spectacular. If they could make these things cheaply in high volumes, solar power could be supplying the majority of energy needs in the future.
Those who research semiconductors these days are exploring ever new clever ways to engineer these materials. Mechanisms for tailoring the bandgaps (by introducing materials that strain the crystal lattice) are becoming more widely used. The three different bandgaps allow photons over a wider range of frequencies to be captured and turned into electricty.
There have been "it's just around the corner!" reports exactly like this one about solar cell tech for more than two decades. Probably even longer, but that's when I started to be interested in solar cells.
Yet, solar cells are still a minor technology, not commonly used. Wake me up when the reports are finally true and buy solar cell powered houses and cars are sold at prices an average consumer can afford and at specifications that an average consumer is interested in.
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You may like my a cappella music
It's not Solar Cell. It's Photovoltaic cell. This is slashdot for god's sake. Should I just call the computer the box on the side next to the TV?
Tim Smith - Ramblings from Nerd Land
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.
It's possible now, but (in the UK) it costs twenty to thirty grand to put a system in. It'll recoup it's cost in maybe 25 years.
The cells you can buy in the stores are more likely to be 15-18% rather than 25% efficient. The 25% ones are fucking expensive and the 35% ones are like rocking horse shit.
Course, energy storage is still a problem for those cloudy days. Batteries are heavy, expensive, made of heavy metals or have to be replaced regularly which isn't exactly "green".
Compressed air energy storage may be feasable on a small scale with the use of a compressed air powered generator, some utilities already use compressed air to store energy on a huge scale. Use solar power to compress air to several hundred atmospheres during the day and run a generator from it during the night and during cloudy periods.
Government of the people, by corporate executives, for corporate profits.
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.
It wouldn't make much of a difference -- they work because the energy of the photons in the light kick electrons off the photoelectric material.
But, light carries the same amount of energy at all wavelengths etc., so making it absorb more just means it would get hotter, not actually generate any more electricity.
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.
If I can store power efficiently, then my solar cells need to generate 18 kWh per day, in about 10 hours of nice, bright sunlight. That's 1800 watts at any given time. At $2/watt, that's $3600 for the array (ignore the storage costs for now).
My electric bill for that month was $55.74, so I get payback in a little more than 5 years.
The problem is, I've seen different numbers for panels. Modules for consumers cost $5.85 per watt, these days. And at that rate, my scenerio costs $10,500, and the payoff time is now 15 years. If I invest that money, and get a 7% rate of return on it, I make more money by PAYING my electric bill ($61.25 per month income, $55.74 payout). It's more profitable for me NOT to install the cells.
The numbers quoted in the previous post for cost drop by growth indicate that (I'd love to see how the math for this is done, properly, but my aproximation follows) those $2 cells will cost $.75 in 2010. Excellent!
But the cost of panels is not all CELLS, and has stayed pretty darn stable. In the past three years, panel cost has only come down a few percent. It went UP some months, too. So we can expect the panels to be cheaper, but not by NEARLY that much.
And in the above I've ignored storage inefficiencies, and support hardware and battery costs.
In other words, I don't think the picture is so rosey.
A solar panel doesn't have to power a house to be useful. 99% of the solar panels I see are on calculators. Replacing batteries on portable devices--what a great use! Presumably, a better solar device, (however you measure better, be it cheap/efficient/durable) will allow a battery-less device to have more smarts.
Cheap solar devices could be educational and communications tools for poor, illiterate areas of the world.
Are we all such good consumer robots that all we can think about is how many gadgets we can power with the roofs of our big suburban houses? This is why someone makes a hot tun with a plasma screen built-in!
What you really want is for minimum ecological impact is a "pumped storage" hydro plant. Build a man-made reservoir at the top of the hill, and a basin at the bottom of the hill. Fill the top reservoir with water. During the day, you let the water flow with gravity downhill through a set of turbines to generate electricity. At night, power the turbines to flow in reverse, and pump the water back up to the reservoir, basically "refuelling" itself.
But, you say, what's the sense in doing that? Conservation of energy says motors use more energy than they can generate in reverse, so aren't you wasting electricity just moving water about? You'll go out of business!
The key is not the volume of water, but WHEN you're generating. In deregulated energy markets like in most of the USA, there is also an ebb and flow to the price of electricity along the day... at night, when people are sleeping, there's too much online supply and not enough people using it, so the price drops... and during the day, when everyone is awake and watching TV and cooking and cleaning and working and computing, the demand for electricity is much higher, therefore the price of energy is higher.
So, generate electricity during the day and have people buy from you at higher rates, and run your pumps at night purchasing electricity from someone else for lower rates. Net, you're making money, keeping your average costs low. Not only that, you avoid erosion and killing fish like you do with conventional run-of-river dams. For an impressive beast of a plant, check out Bath County Station in Virginia.
Green self-sufficient (sum) heating is becoming quite common here in northern Europe. Now we need a personal dc grid for appliances because converting solar to ac and then heating all these ac-dc bricks all around the house seems quite wasteful.
... get real! Some things are just energy wasters.
I think standardizing on something like FireWire 800 wallsockets to universally replace the ac-dc bricks. Most appliances can live on the current allowed by the FireWire standard.
The grid itself would have thicker copper cables to supply multiple FireWire sockets in paralel with enough current to allow each socket to supply the full specified current of 12 Watt.
Most home appliances can make do with 12 watt if you design them that way many waste most of their energy on the power brick:
60 Watt lightbulb = 9 Watt energy saving bulb
75 Watt lightbulb = 11 Watt energy saving bulb
1200 Watt vacuum cleaner = 12 Watt vacuum robot which takes days instead of hours but you don't have to push it around those hours.
1000 Watt dishwasher = 2 Watt dishwasher if it can get water heated with the sunheater next to your solar panels.
2500 Watt washer / dryer
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Dennis SCP
You can do the vast amount of work yourself, save thousands, literally thousands. shop around for the various components. it is no way any harder than building your own peecee, just much larger. You have panels, their mounts, some simple wiring, a charge controller, then usually an inverter/charger for adding grid juice into the mis, and a battery bank. You run the output to your panel box you already have, or just pick a few circuits to power. You can hire an electrician to look it over one day and do the last install to the panel, that's really the only person you need to hire. You *might* need a permit, that varies locale to locale, same as any other home construction action. It's just not that hard if you can use a few normal tools and first sit down and plan out what you need and the steps to take.
As to the batteries, look into a local forklift dealer, look at their traction battery banks for the electric forklifts. Significantly cheaper per amp-hour than deep cells with "solar" printed on them. they come into 12VDC to 48VDC configs, pick out what ya need, it'll probalby run at least 50% under "solar" batteries for the same amp hours.
And look into the new "desulphator" devices to keep batteries and battery banks clean (they run 100-150$ or so), they will keep batteries working MUCH longer than batteries without them, and are very cheap for what they do. I have some deep storage batts I use (some cheap 6 volt golf cart batts, wired in series, then parallel to give me 12 volt dc circuitry) that are still fine,and are already a few years past when they were supposed to go bad according to the literature for them, I got a desulphator and it cleaned them up just spiffy within a few weeks.
The way to deal with alternate energy is work both ends towards the middle, reduce consumption (better apliances, saner useage, better built home with more insulation, better natural lighting, etc), then add in your production, at some point you'll hit a sweet spot where those two personal supply/demand lines cross and you are independent and it becomes very affordable.
And it IS a concern with the politics involved with electricity, and here's something else to consider, with solar (any alternative energy scheme really), you can get an upfront, bottom-line price. With grid supplied, you have zero guarantees on the price a year from now, 5 years, ten years, etc. You are going on a price comparison for looking at years in the future which has no basis in any contract you have, because it doesn't exist. Various areas in the US have had doublings of rates in as little as a one year time span, and it RARELY ever goes down, does it? As far as I know, no utility out there gives a homeowner even a chance at a set carved in stone price/contract for KWH for 10 years from now. You have NO idea what it might cost in the future, nor will you know if it will be even available like it is now, we live in an uncertain world, yes?; and "energy" is sure a politically connected product, so you never know what might happen......
The second consideration is, why do you have to jump to whole house? Just use it as a daily adjunct (for your home office and boxes, it's a great UPS system for example), and as a backup to have *some* power if/when the grid goes down. You might not have enough to run the AC if it's a heatwave and the grid borks, but you can still run some fans, for an example, along with some small appliances, your boxes, a radio maybe, etc. it's a backup for a critical thing for most geeks,, ain't a one of us here DON'T not-like electricity, if I am allowed that double negative. We dig JUICE, so having at least some of your own juice you can control is *slickerissimo*. No law says you have to have either/or, you can have both, just be smart about the first install and scale the components (notably the inverter/charger/controler parts) so you can add to the PV array and the battery banks as you can afford it and have more interest in it. So instead of dropping 20 grand, try 5 with some on site stora
... that's just not true. It is quite easy to make 99.999 whatever percent of cars run on something like ethanol or methanol. A lot of race cars run on methanol, doesn't seem to slow them down any or present any huge problems. Henry ford DESIGNED the model T to run on ethanol, he thought petroleum stuff was way too dirty, and would gunk up the engines (which it does, bad, that's one of the reasons your crankcase lubrication oil gets so dirty) They would burn cleaner, too,much less air pollution, and not even need as much of that expensive computer controlledc crap they put on cars now to make petroleum products burn clean, and your engine would last much longer as well. You could run them on methane, another huge untapped energy source just going begging, using similar pressurised carbs as the quite common propane powered generators use that are installed on farms by the hundreds of thousands now all over the place. A lot of RVs now are dual fuel, propane and gasoline, it's quite common.
If you want to just speak in general terms,
"alternate energy" became practical years ago, the big energy monopolies, and their paid off shills in government, do everything they can to keep people faked out so they can keep getting a check out of you every month forever and ever. Just mandating a doubling of insulation in new homes and buildings via the "building codes" laws they already think up would make energy demand drop severely, but they don't want that, they want your money by the bucketful. I've helped build two super insulated houses, and several heavily modified houses, the energy savings are nothing short of incredible, and the comfort level goes up immediately, and the "payback" is a few years starting with the first months utility bills. You see, "alternate energy" along with it's corrolay "sane useage" and "saner appliances" is greatly suited (in a lot of ways) to smaller independent set ups run by the owners, not some giant public 'service" corporation with their for-profits giant "suppliers", and THOSE guys being filtered through hordes of "commodity traders" who skim off even more mega billions nation wide for doing basically nothing. The REAL problem with alternate energy is joe bigco hasn't figured out how to charge you for "alternate energy" forever like they do with the current "energy" market, because you can actually pay-off your personal production, and they certainly don't want that, they want "vendor lock in" and for you to pay their "subscription",to basically stay as a renter, with no long term price negotiations allowed, rather than an owner with some sort of fixed price, totally in their favor, for perpetuity.
Current estimates of world oil reserves (total)
is around 2 trillion barrels.
The energy stored in a gram of oil (on average)
is 44000 Joules/gram, at a SG =0.9.
1 barrel (oil) = 42 gallons = 0.159 m^3
So 1 barrel has the following energy content,
44 x 10^6 Joules/kg * 998 kg/m^3 * 0.159 m^3/barrel * 0.9
= 6.3 x 10^9 Joules/barrel (6 gigaJoules/bbl)
So all the energy stored in the worlds
oil reserves is,
2.0x10^12 barrel * 6.3*10^9 Joules/bbl =
1.3x10^22 Joules of oil energy.
(2.0x10^12 is a very optimistic value, P=0.1)
Ok, so you think this is a big number ?
The total power radiated from the sun is approx,
4x10^26 watts or 4x10^26 Joules/sec.
The sun radiates the equivalent of all the energy
stored in oil on the earth in,
1.3x10^22/4x10^26 = 32.5 microseconds
The entire oil based world economy (150 years of work)
is only a 32 microsecond job for the sun.
By necessity "we" will become much smarter on how
to capture solar power.
BTW the current world rate of oil consumption
is approximately 80x10^6 barrels/day, at
this rate the remaining 1.5x10^12 barrels
will be gone in, 51 years. The growing South
Asian market will probably help cut this to 30
years, but shifting demand will probably help
keep complete cut off at 50 years.
I have thought of a possible solution, though I don't know if it will work. I would love for someone to try this possible solution, and let me know their results.
Basically, I am thinking of using a piece of alluminum plate/sheet for the back electrode, painting the alluminum plate with copper-oxide containing anti-fouling paint (used to keep barnacles and other things off boats and ships - must have a very high percentage of copper oxide for this to have a chance in hell of working), then, while the paint is tacky, pressing a piece of copper mesh onto it (to form the front electrode) - hook up wires, sandwitch between some clear acrylic, and...profit?
Would this work? Would this be a cheap way of building solar cells? Would it be cheaper than silicon-based cells? Cheaper than used cells (likely not)?
Actually, I know of a way to get real cheap solar panels, which I am currently exploring - hopefully, something good will come out of it...
Reason is the Path to God - Anon
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).
Correct, but misleading. This is a semiconductor technology. It has the potential to obey Moore's Law. Power has been relatively cheap because we're fuelishly burning hydrocarbon reserves, so there has not been the same market incentive for solar cells that we've had for memory and processors. But an exponential growth rate still applies.
Well, it won't be /. news then, will it?
The market ensures that this technology will happen in large scale at the consumer level, barring some new centralized power source such as nuclear fusion. If we were smart, we'd be investing a lot of money in alternative power technologies, (solar, fusion and others), instead of the government being the lackeys of the oil industry and spending a lot of tax dollars to protect a continued supply of oil. Research into alternative energy sources benefits all taxpayers. Protecting foreign oil assets uses tax dollars to benefit only a few energy company executives and sheiks, and even that benefit only exists for the very near future. It's an unfair and unwise use of tax dollars. As a technogeek, the inefficiency and short sightedness of the US energy policy offends me. The previous success of the US economy was based on free market driven technological innovation, not special interest enforcement of the status quo. The US will either look to the future and lead, or cling to the past and follow as others step up to the technological challenges.
>> My ultraviolent Linux switch video.