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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
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.
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
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.
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.
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.
To save you time the babe is on these pictures:
;-)
DS2_0244.JPG; DS2_0243.JPG and DS2_0242.JPG
So you don't have to surf through the other rather boring stuff.
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 $.75 in 2010. Excellent!
But the cost of panels is not all CELLS, and has stayed pretty darn stable. In the past three years, panel cost has only come down a few percent. It went UP some months, too. So we can expect the panels to be cheaper, but not by NEARLY that much.
And in the above I've ignored storage inefficiencies, and support hardware and battery costs.
In other words, I don't think the picture is so rosey.
You can do the vast amount of work yourself, save thousands, literally thousands. shop around for the various components. it is no way any harder than building your own peecee, just much larger. You have panels, their mounts, some simple wiring, a charge controller, then usually an inverter/charger for adding grid juice into the mis, and a battery bank. You run the output to your panel box you already have, or just pick a few circuits to power. You can hire an electrician to look it over one day and do the last install to the panel, that's really the only person you need to hire. You *might* need a permit, that varies locale to locale, same as any other home construction action. It's just not that hard if you can use a few normal tools and first sit down and plan out what you need and the steps to take.
As to the batteries, look into a local forklift dealer, look at their traction battery banks for the electric forklifts. Significantly cheaper per amp-hour than deep cells with "solar" printed on them. they come into 12VDC to 48VDC configs, pick out what ya need, it'll probalby run at least 50% under "solar" batteries for the same amp hours.
And look into the new "desulphator" devices to keep batteries and battery banks clean (they run 100-150$ 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
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.