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New Solar Cell Sets Record For Energy Efficiency
Lucas123 writes "After three years of work, German and French researchers have achieved a new world record on converting sunlight to energy through a photovoltaic cell, achieving a 44.7% rate of efficiency, which was measured at a concentration of 297 suns. The efficiency rating means the solar cell collects 44.7% of the sun's spectrum's energy, from ultraviolet to the infrared spectrum, which is converted into electrical energy. The team of researchers said the technology places them on the path to achieving their roadmap of 50% efficiency in solar energy conversion."
At cleantechnica site you can see a priced drop of $76/w to under $.74 a watt in only (sorta wish it was .76 a watt for neatness sake, dontcha?)
http://cleantechnica.com/2013/05/24/solar-powers-massive-price-drop-graph/
You can also see a similar exponential but reverse growth curve off a link from that page.
Elsewhere, I saw solar was projected to generate more energy than the U.S. currently generates by 2050-- and to quintuple from there by 2100.
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Loved "Mystery Men". On my top 100 list.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
Sure, the Germans get better solar efficiency, they get a lot more sun.
Look at the graph at http://en.wikipedia.org/wiki/Solar_cell_efficiency (about half way down). All the multijunction solar cells are run under concentration ranging up to ~1000 suns (1000:1 focusing of the suns energy). What's really impressive is that they are getting closer and closer to the 86% efficiency limit imposed by Carnot. Just like with Wind (~59% limit imposed by Betz's Law), our solar cells are approaching as good as we can get.
Here is a graph of solar cell efficiency showing the different kinds of materials used to make them. The typical solar cell is silicon (blue on the graph) and maxes out at 27.6% efficiency.
Anons need not reply. Questions end with a question mark.
Multi-junction cells are expensive to produce, using techniques similar to semiconductor device fabrication, usually metalorganic vapour phase epitaxy but on "chip" sizes on the order of centimeters. In cases where outright performance is the only consideration, these cells have become common, they are widely used in satellite applications for instance, where the power-to-weight ratio overwhelms practically every other cost.
Anons need not reply. Questions end with a question mark.
No. But the Saudis are investing in cloud technology.
"...a photovoltaic cell, achieving a 44.7% rate of efficiency, which was measured at a concentration of 297 suns"
This means that they use mirrors to focus the light onto the panel. Since high-efficiency panels tend to be expensive, the more light you can concentrate on it, the better. The fact that it can handle a near 300 fold increase in throughput is a good thing. These are not going to be used on a residential roof flat panel anytime soon.
Yawn...
Another day another solar cell breakthrough that wont see the light of day (see what I did there) for 10 years if ever.
Why is it none of these ever make it to manufacture. Typical solar panels have an average efficiency of 15%, with the best commercially available panels at 21%.
Yet we get a new announcement weekly.
Sig Battery depleted. Reverting to safe mode.
It will take a while for the technology to hit the manufacturers but it will hit panels for satellites first. When you are paying $20k per pound (0.5kg) to put something in space if you can get a higher efficiency with less weight you can pay a LOT more for the panels and still come out ahead.
I do not think pholtovoltaics are limited by the Carnot efficiency, which applies to the conversion of heat to mechanical work in heat engines. The energy stored electrochemically in batteries can exceed the Carnot efficiency, as can fuel cells.
Not much point in comparing the efficiency of an energy source with the efficiency of an energy sink; they're at the opposite ends of the energy cycle.
Unless you can use your solar-electric power immediately, you also need to add a whole conversion system for storage and discharge which can be quite lossy if you choose electrolysis for energy storage due to much higher energy density than batteries.
To make a fair comparison, you would need to pit two options with similar energy cycle against each other. Something like solar-hydrogen vs solar-biodiesel or solar-ethanol. Growing algae and converting it to biodiesel or ethanol to keep internal combustion engines running might be more efficient overall than electrolysis to produce hydrogen before converting that back to electricity to drive electric motors. Ethanol and biodiesel also have the benefits of well-established distribution channels while high-pressure hydrogen is still scary for many people.
I'm not including plug-in electric since everyone I know seem to be highly skeptical of their operating range and seriously worried about battery replacement costs that can quickly wipe out any fuel savings.
This means that they use mirrors to focus the light onto the panel.
I know just where to put them.
http://news.slashdot.org/story/13/09/03/0157256/building-melts-car
It's not really efficiency that determines the profitability of solar cells. It's the ratio of Efficiency / $. These might be the most efficient ever produced, but they're likely substantially more expensive than the 15% variety (i.e. 3x more efficiency at 10x the cost).
It really depends on your local power company NET/FIT rates, federal solar panel import protections and state/city building/code regulations.
Some areas ensure you get real cash back for feed in back to the grid. Others have do not offer so much export cash to homes with solar.
City building/code regulations can also be costly in some areas.
http://freeingthegrid.org/
http://en.wikipedia.org/wiki/Net_metering#United_States vs http://en.wikipedia.org/wiki/Feed-in_tariff#United_States_2
http://finance.yahoo.com/news/solar-panel-next-granite-countertop-161321343.html
http://www.fool.com/how-to-invest/personal-finance/home/2013/09/15/net-metering-how-a-little-known-policy-can-shave-h.aspx
When energy prices going up, you get a FIT, the cost of a solar install in your state is fair, your home has newer appliances... the pay back period is not so unaffordable over years.
Domestic spying is now "Benign Information Gathering"
"Germany's Energy Poverty: How Electricity Became a Luxury Good" Spiegel 09/04/2013
German consumers already pay the highest electricity prices in Europe. But because the government is failing to get the costs of its new energy policy under control, rising prices are already on the horizon. Electricity is becoming a luxury good in Germany, and one of the country's most important future-oriented projects is acutely at risk.
In the land of the blind, the one-eyed man is king.
Do you get your talking points from a PR firm? Did you seriously just list the price of re-shnging your roof as a reason why solar could never be economical? Even if that were true, you need to think outside of the box, brah. http://cleantechnica.com/2013/05/15/caution-wet-solar-power-new-affordable-solar-paint-research/
I find it pretty comic you're listing today's absorption rates as the reason solar "will never" (emphasis on the bolded word) be affordable. What website are you on right now? I wouldn't peg you for a technology enthusiast. Got news for you, bud: technology advances. Solar will become a dominant energy source. It's just a matter of when. You should stop watching cable TV; it's convinced you of silly things, sheltered you in petrol pipe dreams.
Why is it none of these ever make it to manufacture. Typical solar panels have an average efficiency of 15%, with the best commercially available panels at 21%.
Because as much as I look forward to someday powering my entire house with a handful of 90% efficient solar panels, I care a lot more about the cost per panel at present. If I can afford to pave a quarter acre with 10% efficient panels while these 40%+ ones would bankrupt me - Hey, guess which ones I'll just buy 4x as many of?
Sunlight at high noon directly overhead is close to 1000 watts per square meter. My neighbor's roof has panels about 2x4 ft (a bit less than a square meter) that are rated at 120 watts output each. Her rooftop array of just a dozen panels provided 100% of her consumption last year, per her net metering annual bill.
It's a very modest sized house, One bedroom, one bath, about 1000 square feet, but it is also a very modest sized array.
They use Fresnel lenses, not mirrors : http://www.soitec.com/en/technologies/concentrix/components/
PS: I worked with Concentrix (now Soitec). Cool company.