It’s May day, You have just hours before you go to Dinner with your Spouse and a leading expert in the Field of CPV, what will you read in order to at least act half way interested, and perhaps even engage him in a conversation about his technology and interests? You know he has no interest in sports, or what hollywood does, it’s going to be a long and awkward evening less you take a few minutes to prepare.
I suggest you read along, it’s a short read, but it does require you look at a few webpages, but I promise it will be near painless.
If you are old enough, you’ll remember the round head lights we had in cars for so many years. The lights were called sealed beams and they concentrated the light from the element and focused it into a specified area. The sealed Beam head lights used in Autos are noteworthy because they worked so well AND they ‘concentrated’ light just like a CPV system does.
I’m not sure when it was, but somewhere in the 80s, the Automotive Engineers had a better idea, maybe it was style driven, maybe some of the Engineers who were after superior aerodynamics liked them as well, but no matter how few or how many reasons, the newer units took over. The glass enclosure now had an opening in the back, and there was a smaller light bulb that could be pulled out the back and replaced when it was bad.
It took only a bit of time for people to realize the downside of these new lighting units, a rock chip could and did break the seal of the enclosure, and when you pulled into your drive at night and turned off the key, the light would cool and often drew in moist air. The next morning when the air temp picked up a bit, the moisture inside the head light enclosure would condense and make a soup of sorts. This could lead to growing a culture of algae like green, red, and might even help remove that few microns thick of shiny stuff on the back called a reflector.
Soon, a lot of folks were driving down the road thinking they’re going blind, some checked in with their car mechanics and found that the lighting enclosure had been compromised and needed to be replaced because it no longer concentrated enough light for one to safely see at night The Owner often said OK, replace them, call me when you’re done.
This lead to owners going into shock when they were presented with a $300 plus bill (in the 80s remember). The new enclosures were $120 and up each, and that didn’t include installation, or the new light bulb. They were expensive for a reason, part of it was they were sealed from the elements that can and do destroy or rapidly degrade the reflective elements that concentrate the light.
This caused a lot of people to think about what they had lost with the old system, as it was just a few dollars for the entire unit, and they were quick and easy to replace. The first aftermarket plastic covers came out to snap over the head lights to save you from rock chips that were VERY common. The plastic got dirty, the sand and grit wore the surface and cut the light transmission, they aged in the Sunlight and turned yellow too. Soon, people couldn’t see again, and thought they were going blind.
There was another problem, after some years, the plastic holder for the light bulb wore, and so did the O ring, when it started to leak, you could bring in the moist air, and foul or lose your internal reflector coating by growing a culture inside. I personally know people who do not drive at night anymore than they have too, it scares them, and they think it’s their failing vision, hard to convince them their concentrating system has degraded to the point of being dangerous.
All of this is a lesson that it takes a while for a concentrating light unit like I describe to show us both the advantages and disadvantages, and there is no doubt in my mind that this new system added to the cost of car ownership.
The discussion of concentrating light beams is about lenses, mirrors, and little more, it can work well WHEN the environment is sealed and moisture, dust and dirt have no chance to get in. Of course what one man calls sealed, another won’t and the discussion can get down to “sealed for how long?” then, we get into the lens material, there’s glass, and many types of plastic, some plastics are wonders, and they stay fairly clear for years, and the biggest problem comes when they aren’t cleaned with the utmost care. If they’re loaded up with sandy grit and you attempt to rub them clean with a dry rag, it can turn ugly. Not only have you scratched the surface, but you may have made it toothy to the point where bacteria can set up housekeeping and further impede light transmission. Glass sounds like a great choice, but what about 50 MPH winds and dust storms?
In concentrated PV, we have the same issues as we do with a common auto head light, only we multiply any problem with degradation of the light transmission path 10,000 times or more from a maintenance point of view.
In concentrated PV, we have the same issue with pointing the CPV panel at our light source, it’s reverse of pointing our light source in the direction of travel, but very similar. In the car, we turn the steering wheel, in CPV, we have electronics that know where the sun is, and make use of gears, hydraulics, servos, or a number of other parts to make sure the sun is aligned accurately with the lens, and concentration elements, when this doesn’t happen, no electricity is made.
There’s other automotive data you might consider. People here in Washington State who commute daily over our mountain passes are normally forced to replace their windshields annually. This is because they can become so sandblasted that they are literally dangerous. What is it like in areas where CPV is deployed? Wind speeds, driven sand and dust?
This is all about light being able to get through a lens, or a clear cover, and how reflectors degrade, in autos, they degraded far more rapidly than some thought. How will the Concentrator elements in the CPV systems perform, and what problems might already be showing up in Hatch for instance Does anybody care to know?
Now it’s time for you to do a few web searches, it’s all so easy, and we’ll assume you use google since most do.
http://en.wikipedia.org/wiki/Concentrated_photovoltaics
Now that you have a little back ground, just hold the analogy of a rifle scope, all is well when you have the scope on the cross hairs, all is in focus, lenses are clean, and the solar cell is working of course.
If you do a few more google searches, there’s little chance you won’t run across this site http://amonix.com/content/solar-pioneers
Why not use the touted leader for our study? We form the questions you’ll entertain your expert with. We know we don’t have the answers, but decent questions will allow us to express some interest in the topic.
Potential questions follow:
Hey, I ‘ve seen the Las Vegas Sun has been covering Amonix all along, and isn’t it great we have those huge deployments in Alamosa Colorado and Hatch New Mexico! What I’m curious about is why they all of a sudden dropped the Coverage of Amonix just when they have something to show off?
I hear the wind blows pretty hard in Hatch New Mexico, and the air is so full of sand, dirt, and grit, this ought to be a great place to prove how well the product is doing, how do we find out? Are these solar modules holding up well, how many have they had to replace? Any wind damage? I’ll bet the whole CPV community is discussing this somewhere, where do we find the conversation?
Hey, when is the factory in Las Vegas going to roll out the next batch of product? I see the Los Vegas Sun hasn’t said a word about Amonix since they announced all the job layoffs there, what’s up with that?
Amonix, the leader in CPV, and with enough trackers in the field to prove just how good they are. This is a fact as far as I can access.
Let’s look over this claim:
http://amonix.com/content/no-water-operation
No water used for cooling, impressive savings? Do we really save a valuable resource?
More questions for our Professionals, and maybe we go right back to the Automotive World and look for analogies? CPV is a power plant, so are air cooled engines and water cooled engines, have you ever seen an air cooled engine maker advertise that they are saving a valuable resource by avoiding the use of a water cooled engine?
I think the average man or woman notices there’s no garden hose hooked to the car, and perhaps there’s very little water in the cooling loop, and not so much of a loss, it does beg thinking people to ask, just what group of people was this page designed for? It’s not an answer, just another question for our professional.
Of course this leads to more questions, and that is, we know that near all of the automotive industry has adopted the water cooled engine, and now we see that the majority of motorcycles have gone that way. The whole point is to carry off waste heat, and allow the machine to operate at a more ideal temperature. We learn from the WIKI page that heat is a problem with efficiency, and by cooling the CPV modules we can increase efficiency.
This leads to another question we ask our professional. Isn’t the whole idea of a CPV system that it is more efficient? If this is true why is the problem in the CPV different than in the automotive engines, and why have the Automotive engineers who have been dealing with the problems of carrying off excess heat to assure both efficiency and longevity of their equipment finding water or liquid cooling the more ideal answer?
Isn’t the problem exactly the same? Shouldn’t the CPV engineers recognize the automotive Engineers have about 130 years of experience in optimizing their cooling systems, AND have given up on what Amonix has deployed in their current tracker?
I remember sitting in a 1976 Fiat, and I noticed they had used some optical fibers to actually report on whether the head lights were on, innovative I thought, a different approach, but who could argue the stake holder (the one behind the wheel) could tell both lights were working.
This creates more questions for us:
How automated is the leader in the field? How do you know if a module has over heated and burned out, or is not performing as we expect? Is there any remote way of telling if a cell is bad, and how much effort does it take to get to the cell and replace it?
Do we break any seals getting in and out to replace it? Do we need wait till the blowing dust and dirt stops to do it?
Where is the group of people who care what the actual performance of these panels are? If the US Government has given any incentives at all to Amonix or those who bought and deployed the product, should we Citizens enjoy the privilege of learning how they are working in the field?
Why is it that EVERY Green Energy Site I can find looks more like a place to market Green Energy, and not to discuss the technical merits of the product?
I’m sure the DOE has the results of this deployment at Hatch for instance. do we have any right to know?
added 5/8/2012: I see the NREL has posted comments on Amonix, here’s an example:
Cost savings were factored in every step of the way — from foundry to grid — said Bob McConnell, who worked at NREL before he left the lab in 2007 to join Amonix and help bring the research to market.
The result is a generator manufactured at about a third to one half of generators using crystalline silicon or thin-film approaches.
Multi-junction cells can operate at higher ambient temperatures than traditional PV cells, making them ideal for sunny and dry climates in the southwestern United States, and ripe for future cost reductions.
The concentrator also is kinder to the environment than most large systems, using no water in its operation. Propped up two feet above the land, it doesn’t hinder the movement of wildlife.
“You simply can’t put enough solar systems on rooftops to achieve the scale and capacity necessary to generate electricity in the quantities required by utilities and by society,” said Amonix’s founder and chief technical officer, Vahan Garboushian. “This is a technology that can meet the terawatt (trillions of watts) needs of the world for clean electricity.”
As we attempt to digest what the NREL writes here, does it seem the relationship is a little like a marriage between first cousins? I mean the mention of the water savings again.. just how much water do you save in a closed loop glycol system? And don’t we know there would be a lot of consideration to using a lifetime waterless coolant as well. Some who read this will see it more as an advertisement. I think it might cause some of us to question the NREL’s mission.. but hey, I only have the questions here.. not the answers..
G