solar milestone

[StressMan79]

I just saw this posted in by Boeing (Boring) News:

TopSpectrolab sets world record for solar-cell efficiency
Spectrolab, a wholly owned subsidiary of Boeing, today announced that a solar cell it manufactured has set a new world record for terrestrial concentrator solar-cell efficiency. The cell can convert 41.6 percent of concentrated sunlight into electricity. The U.S. Department of Energy independently tested the efficiency of the Spectrolab cell in June, validating that it surpassed the previous record of 41.1 percent, held by the Fraunhofer Institute in Germany. ?This latest record asserts Spectrolab?s leadership position in high-efficiency multijunction solar cells and brings the industry one step closer to achieving affordable solar electricity,? said David Lillington, president of Spectrolab.

so you can say that the maximum solar cell efficiency on earth is not even 42%.

-peter

[rreidnauer]

so you can say that the maximum solar cell efficiency on earth is not even 42%.

-peter
For example, my Sharp NT175-U1 moncrystalline panels have an individual cell efficiency of only 16.2%. (overall panel efficiency is only 13.5%) The rest is converted to infrared and is either reflected or passed through the panel. But really, I find it silly that it even matters when your energy source is unlimited. What does it matter if a panel passes on a significant amount of available energy, as long as you get the watts you're trying to extract. I saw one online seller pushing (more expensive) panels with slightly higher efficiency ratings, of similar wattage output. To the consumer, panel efficiency really means nothing as long as you're getting the advertised watts.

Now, one reason higher efficiency helps is watts per square foot. If you can get more watts out an array on a limited amount of roof space, this is a good thing, but closely note the article says "concentrated sunlight." That means they are directing an area of sunlight larger than the array itself. (probably with mirrors) I could do the same and boost my performance, but at the cost of additional heat risking damaging the panels and no doubt, shortening their lifespan.

[clairenj]

that were made in Australia and banned from sale her in the US? Do you think that was the problem, the concentrated heat? I kind of dropped the ball on that research I was doing. Just curious if you know anything about them.

[edkemper]

Help me understand the significance? What is the efficiency of the "normal" cells we can buy?

[StressMan79]

them to be less than 20%, for you and me, efficiency is not a big deal, as you will prolly have acres of are if you could get 1% panels free... Like Rod said, so long as the wattage is as advertised, it will likely not make a big difference to a homeowner...

However, if your home is a satellite, and space and weight ARE at a premium, then efficiency DOES matter, which is why boeing is pushing the envelope.

anyway, it is often good to bound the problem.

FYI, solar irradiation is usually ~1000W/m2, and it shines roughly 6 hr/day (effectively at full strength) so if you are getting 15% efficiency, and you want 60kwh/day, you will require 66m3, or a square roughly 26' on a side. If you were on the grid, this much power will only cost you roughly $6.

-Peter

[Yuhjn]

The mars rovers that lasted years longer than expected had solar panels with 27.5% effeciency at beginning of life.