IBM Concentrator PhotoVoltaic (CPV) Solar Power Research Breakthrough
by John Laumer, Philadelphia on 05.17.08
IBM has leveraged their computer-chip cooling know-how into a highly effective solar concentrator design. Bench-scale testing of the design (as pictured) shows an order of magnitude increase in solar power output from a unit cell. Other designers have worked out CPVs with similar concentrating lenses, typically paired with a tracking device. The cooling part of IBMs' design is the cool part: something no other designer has access to, presumably.
The trick lies in IBM’s ability to cool the tiny solar cell. Concentrating the equivalent of 2000 suns on such a small area generates enough heat to melt stainless steel, something the researchers experienced first hand in their experiments. But by borrowing innovations from its own R&D in cooling computer chips, the team was able to cool the solar cell from greater than 1600 degrees Celsius to just 85 degrees Celsius.
The initial results of this project will be presented at the 33rd IEEE Photovoltaic Specialists conference today, where the IBM researchers will detail how their liquid metal cooling interface is able to transfer heat from the solar cell to a copper cooling plate much more efficiently than anything else available today.We wonder if they will sell only Mainframe Panels and if Apple will beat them to the Personal Panel market as a result?
Via::IBM, IBM Research Unveils Breakthrough In Solar Farm Technology - “Liquid Metal” at the Center of IBM Innovation to Significantly Reduce Cost of Concentrator Photovoltaic Cells
Many unanswered questions!!!!
Does the concentrator increase the efficiency of the solar pannel above 20%?
How much power does the unit generate??
If the concentrator produces so much heat, why not use it to power a sterling engine??
Maybe they could transfer that heat to water for storage, or just general heating needs?
Good questions Neil! I'd like to add,...
* why not use thin film thermoelectrics like those produced by RTI? This would be a small part that could passively collect electricity, control the temperature to precise values and if needed, cool the system as well. All this and it has no moving parts either!
Would be interesting if they could take that heat and use it for some sort of co-generation of thermal solar power.
The most important point seems to be that
"the IBM system cuts the number of photovoltaic cells and other components by a factor of 10." (taken from the press release). This makes the system much cheaper than those currently available.
The solar panel, however, seems to be conventional. The efficiency will therefore be below 20%. I guess, the actual efficiency is lower than that of "normal" photovoltaic cells w/o the concentrator. However, if you have a lot of space but not much money, it's still nice.
Ooo I like the star cut-outs on the inside of the dome thing. I hope all of their solar panel systems have them :D
Seems that the process is much better than current CPV technology - and unless my math is bad around 30% instead of 20%. Other questions answered in the article ...
This is pretty cool, i wish I had one. :)
Already invented by an Australian 3 years ago(note the award 2005 top right) see http://www.greenandgoldenergy.com.au/
so why is IBM saying it's a breakthrough.
The Suncube also gets 34% efficiency, and he is selling the rights to make them all over the planet. An Indian factory to be operational in 2- 3 months, how log are you going to have to wait for IBMs product to get to the market
there are research pv cells in the 40% efficiency region....
a major advantage of concentrator technology is that it cuts
the requirement for expensive pv cells...but with
concentration i would expect it to be viable to use more
expensive/advanced pv cells
regards
This is used for "large" concentrator cells of 1 square centimeter. If you optimize the cell based on the actual atomic-level performance with series resistance losses and edge recombination, the ideal cell size is actually closer to 1 square millimeter. (reference a recent book called "Concentrator Photovoltaics") What's exciting about this is that concentrators using 1mm^2 cells don't actually need active cell cooling at all! (Also reference "Concentrator Photovoltaics")
This is definitely good stuff, but the concentrator pv systems that'll eventually make PV cost-effective will use very small cells to entirely eliminate additional cost of cooling hardware while actually boosting cell performance. Check out this company: www.solfocus.com
Also, conversion efficiency of concentrator modules are now approaching and exceeding 30% including all losses. These systems have easily projected costs below $2/watt which beats any 1-sun cell applications. This is such an exciting time for PV technologies!
Green and Gold guy designed a PV solar concentrator lens/tracking system to track the sun and focus it to a few high output (and expensive) solar cells.
IBM figured out a way to cool it while developing the same type of technology. I'd assume it would lead to a higher efficiency but I'd need to RTA to find that out.
Off to read the article....
Many IT giant now turn to doing solar, including Google.
how about transfering the heat to water in piping the walls of buildings and homes...
If I were building a concentrated PV system and needed to keep my cells cool, My first thought would be to back it with a Peltier that's powered by the cell it will be cooling.
This technology uses a liquid metal to transfer heat much more effectively than conventional methods. The metal achieves 100% contact and conducts the heat to a cooler source much better than conventional heat sinks. This allows concentrated solar that would melt most solar cells. IBM's trick does not produce more power - it allows more solar energy to be concentrated on existing cells, which results in more energy converted. Its not exactly a linear improvement, but putting 2000x more light in the same space will result in a serious boost at a much lower cost that current methods.
If you're using expensive liquid-metal conducting, recapture of waste heat is really of secondary importance. After all, if you recapture the heat, it slows down the cooling system, which requires it to be bigger, which is thus more expensive and self-defeating. And Stirling also requires a cold sink of equal magnitude, which is probably not readily available. EG -Recapturing auto exhaust with a turbo makes the car more powerful, but not necessarily more efficient.