Posted on 01/10/2005 12:07:43 PM PST by ckilmer
New plastic can better convert solar energy Canadian Press
TORONTO — Researchers at the University of Toronto have invented an infrared-sensitive material that's five times more efficient at turning the sun's power into electrical energy than current methods.
The discovery could lead to shirts and sweaters capable of recharging our cellphones and other wireless devices, said Ted Sargent, professor of electrical and computer engineering at the university.
Sargent and other researchers combined specially-designed minute particles called quantum dots, three to four nanometres across, with a polymer to make a plastic that can detect energy in the infrared.
Infrared light is not visible to the naked eye but it is what most remote controls emit, in small amounts, to control devices such as TVs and DVD players.
It also contains a huge untapped resource -- despite the surge in popularity of solar cells in the 1990s, we still miss half of the sun's power, Sargent said.
"In fact, there's enough power from the sun hitting the Earth every day to supply all the world's needs for energy 10,000 times over,'' Sargent said in a phone interview Sunday from Boston. He is currently a visiting professor of nanotechnology at the Massachusetts Institute of Technology.
Sargent said the new plastic composite is, in layman's terms, a layer of film that "catches'' solar energy. He said the film can be applied to any device, much like paint is coated on a wall.
"We've done the same thing, but not with something that just sit there on the wall the way paint does,'' said the Ottawa native.
"We've done it to make a device which actually harnesses the power in the room in the infrared.''
The film can convert up to 30 per cent of the sun's power into usable, electrical energy. Today's best plastic solar cells capture only about six per cent.
Sargent said the advance would not only wipe away that inefficiency, but also resolve the hassle of recharging our countless gadgets and pave the way to a true wireless world.
"We now have our cellphones and our BlackBerries and we're walking around without the need to plug in, in order to get our data,'' he said.
"But we seem trapped at the moment in needing to plug in to get our power. That's because we charge these things up electrically, from the outlet. But there's actually huge amounts of power all around us coming from the sun.''
The film has the ability to be sprayed or woven into shirts so that our cuffs or collars could recharge our IPods, Sargent said.
While that may sound like a Star Trek dream, venture capitalists are keen to Sargent's invention.
Josh Wolfe, managing partner at Lux Capital, a New York City-based venture capital firm, said while such a luxury may be five years away, the technology knows no bounds.
"When you have a material advance which literally materially changes the way that energy is absorbed and transmitted to our devices... somebody out there tinkering away in a bedroom or in a government lab is going to come up with a great idea for a new device that will shock us all,'' he said in a phone interview.
"When the Internet was created nobody envisioned that the killer app (application) would be e-mail or instant messaging.''
Sargent's work was published in the online edition of Nature Materials on Sunday and will appear in its February issue.
yes but......
I hiked into remote locations within the Philmont Ranch, a high adventure camp of the Boy Scouts of America, and was astounded to see solar panel powered water pumps in the far backcountry camps. The solar power replaced the somewhat unreliable wind mills used before.
In this application, batteries charged with the reliable New Mexican sun was cost effective and excellant use of the technology. Running power lines was out of the question. I was told the wind mills were high maintenance devices and could not be counted on to pump up the required water, and made a lot of noise. When they worked, ok but no wind, no water.
Also, on a subsequent trip into the southwest, I noticed similar solar arrays on Navaho houses far out in the boondocks. I was told the Navaho Nation generated electric power with it's own coal but some customers were too remote to justify running wire. I assume loads were light but perhaps adequate for a satelllite tv and a refrigerator.This also seemed like a good use of the technoloogy and of the unceasing Arizona sun.
I understand your points but now that the technology exists, perhaps there is a bright young mind that can develop some applications out of the mainstream.
For the record,although I have Mother Earth (as in Mother earth News)tendencies, I worked hard building big time steam and nuclear generating plants.
"If anything this is a waste of research money when it come to making electricity. The money would be better spent on design improvements to conventional power generation to improve the efficiency of fuel used to electricity out."
We are spending about $5 billion a MONTH in Iraq mainly to help perpetuate our addiction to petroleum and "conventional power generation". The big picture is this: the current global rate of energy consumption, about 13 terrawatts, is roughly equal to the radiant solar power received by the surface of Lake Michigan. If we were spending anywhere near $5 billion TOTAL on harnessing solar energy, we could quickly free ourselves from forever sucking on this oil-filled tit.
| 8 | “Researchers at the University of Toronto have invented an infrared-sensitive material that's five times more efficient at turning the sun's power into electrical energy than current methods. The film can convert up to 30 per cent of the sun's power into usable, electrical energy. Today's best plastic solar cells capture only about six per cent.” |
It usually doesn't take much reading of these "solar power miracle" discoveries to find where the numbers are being fudged and where the truth is hidden, and this article is no exception.
Yes, 30% is five times bigger than 5%, but "today's best plastic solar cells" is not the relevant comparison. The relevant standard of comparison is to today's poly-crystalline solar cells which have an efficiency of 15%. Thus, this discovery might give you up to twice the efficiency.
The problem is, that this discovery is not nearly enough increase in efficiency to make solar power practical. Observe...
Where your connection to the electric utility grid is either non-existent or problematic, solar cells can offer a practical solution. However, when used as a supplement to, or replacement for the grid, there is simply no rational economic way to justify the use of photovoltaic cells...
ref.
source
loss
(%)power
(per m2)
1.
Solar flux
1,368 W
2.
Atmospheric losses
752 W
3.
Night times losses
376 W
4.
Solar angle losses
188 W
5.
Cell conversion losses
22.6 W
6.
DC®AC inverter losses
20.3 W
7.
Net efficiency
1.5%
8.
Net energy (per m2 per day)
0.5 kWh
9.
Value of energy (per m2 per day)
4.3 ¢
10.
Solar panel cost (per m2)
$530
11.
Payback period
33 years
Notes:
1.
Above the atmosphere. Compare to solar constant.
2.
Loss = atmos. absorp. + atmos. reflect. + cloud absorp. + cloud reflect. See additional references: 1, 2, 3,
3.
Necessary for calculating average daily value of energy production.
4.
Effect of solar angle on efficiency. Line 4 equals 4.5kWh per day. Compare to U.S. Average Daily Solar Radiation.
5.
Shell SQ175-PC, including specified de-rating for cell temperature and irradiance level.
6.
5kW modular, certified, grid-interactive, inverter.
7.
Line 6 divided by line 1.
8.
Line 6 times 86,400 and divided by 3.6E6.
9.
From 2004 DOE stats for average U.S. residential price.
10.
Shell SQ175-PC solar panel, $699, 1.32m2 area.
11.
Exclusive of installation, inverter, interest, etc.
Real World Performance...
Shell Solar offered a peak at real-world performance in their document: "Solar Electric System Case Study". This document reports on the performance of a roof top residential installation in sunny Southern California. The array consists of 32 Shell Solar SP75 solar panels.
The report states that the total projected system electrical energy output per year is 3650 kWh. Using the data from the Shell report and the spec sheet for the SP75, the average power production is 20.6 W/m2. A comparison between that value, and the nearly identical value of 20.3 W/m2 quoted in line 6 of the above table, suggests that the table data is a highly accurate approximation of what one can expect from solar power.
The SP75 solar panel price, is $349, so an array of 32 panels would cost $11,168. At current California residential retail utility prices, 3650 kWh of electrical energy, is worth $432. That places the payback (breakeven) period at 26 years.
In other words, this technology is so expensive, that you won't begin to "reap the benefits of cheap, inexhaustible, solar power" for over a quarter century! Moreover, when the cost of installation, power inverter, wiring, building permits and interest are figured in, that payback period will be at least twice as long as stated.
Many owners of residential roof top installations report much lower costs than those described above. The explanation is that the government sponsors, and you fund through taxes, solar power rebate and incentive programs that are used to hide the real costs of massively inefficient and over-priced solar power.
--Boot Hill
At 30% efficiency, and a grid spacing of 25% to allow maintenance in and around the panels, you would only need an area of 297,000 square miles to supply all of Earth's current needs (based on your Lake Michigan comment, can you provide a link to data supporting that?). If you doubled the area and made the panels a belt around the Equator you'd have power without much of a diurnal cycle.
You may want to double the area again to allow for clouds and local problems- that would only be 1.18 million square miles of solar panel, or a belt fifty miles wide circling the globe.
If you made it 60 miles wide, you'd cover future needs.
You can bet with a setup like that efficiency would not be a cost driver, but consider the benefits to everyone.
Broken down to real terms it does not sound all that impossible.
solar power rebate and incentive programs
.............
Absolutely. The number I threw out above, 8K$ for a 2500 watt system, was quoted to me as the price after rebates and incentives and deductions, all tax funded.
If I wanted, and my local utility allowed it, I could install a special utility meter that I could use to sell power back to the local utility, at a mandated rate much higher than their wholesale rate (the other line users then pay higher rates, or the utility loses money). This was all based on the Carter era alternative energy laws. My solar hot water setup was "free" back then after all the (tax funded) kickbacks.
tanstaafl.
Well, your data as it relates to cost is based on a diferent technology, I don't know how much this new plastic will cost... It sounds like it would be cheaper than the old method
and more effecient... I don't think this could be used as a replacement for the grid but it could be used in conjunction with, IF they can get the cost of these cells down I think it it could be worth it.
Whether dealing in physics, economics or politics, we can't be reminded of that truth often enough.
--Boot
Coat roads and highways with this stuff. Make use of all the infrastructure out there. The DOT/states/counties could sell enegry back into grid, pays for road repair and upkeep.
and you could drive around in electric cars that have a "brush" touching the road. Like giant slot racers or "bumper cars". hehehe
well.. I don't know how well it would sitand up to road traffic but, I could see then putting cells along the highway,
you know like they have powerlines along the highway... this way if they had a problem they could get to it easily and do repairs... hmmmm.... And we have lots of highway to line bothsides with panels :)
| 8 | “your data as it relates to cost is based on a diferent technology, I don't know how much this new plastic will cost... ” |
My data for the poly-crystalline technology describes the cheapest photo-voltaic conversion process currently available. As of this date, plastic thin-film technology is considerable more expensive. Take a guess why the authors of this article didn't estimate the cost of this new technology!
--Boot Hill
True, I wish they would have put a price tag on it.
Because it's difficult to guess how much technology might cost in the future? In 1968, a transistor cost $1 (and that was a 1968 dollar). A dollar now will buy upwards of fifty million transistors. It's not likely that future manufacturing processes will drop the price of plastic-film solar panels to such a small fraction. However, it is not unreasonable to theorize that this technology might become cost-effective if invested in.
| 8 | “it is not unreasonable to theorize that this technology might become cost-effective if invested in.” |
You be sure to ping me when that happens! And when you say "invested in", that's the current euphemism for tax supported boondoggles. Yes, estimates about costs are difficult, but when there is even a prayer that it might be a competitive technology, they will hazard an estimate. In this case, they gave us nothing.
--Boot Hill
Yes, estimates about costs are difficult, particularly when you ignore future costs. When we finally have to use tax dollars to save the human species from choking on its own excrement (assuming its not WAY too late already), will that be a "tax-supported boondoggle"? Does that not factor into the current cost of fossil-fuel energy use?
At 30% .... you could line the inside of caves and use fire or fission piles to keep everything hot and extract electricity.
Anyone know what the efficiency of electricity from a heat source is using a turbine ?
This could replace a LOT of intervening steps in making electricity in the 3rd world.
No, this is bigger than that. Like the microchip.
Think how much infrastructure is involved in creating generators, steam turbines and the machining of all that in order to create a power plant.
All that just went out the window.
Imponderables are just that, imponderable. You can't factor in an "if, then", by just presuming that the if statement is true.
--Boot Hill
lso, a third of the USA is desert. It would be nice to expand the habitable part of the USA too.
Ah, but you're forgetting the Desertlands Preservation Act
of 2006!
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