Cool Earth Solar CPV "Solar concentrator"

[DennisLoi]

This company claims that their "solar baloons" can concentrate solar with a plastic lens in a small solar cell and thus achieve higher efficiency(?). I think this is bs, any thoughts?

I have attached an image from a news article (source, in italian: https://www.jedanews.com/globi-solari-gonfiabili-costano-due-dollari-ma-sono-400-volte-piu-efficienti-dei-pannelli-500-watt-di-produzione-energetica/?fbclid=IwAR10akUhRhDqLVRO_O-QvnuQTg2o7Hv_vP5phiBVoPtbDOy0zhJxXgboox8


In the same article they claim that they produce 500W and thus 400 times more efficient than a regular solar panel

Edit:
I've found a 2008 article on cnet
https://www.cnet.com/culture/cool-earth-solar-generates-power-with-solar-balloons/
I'm sorry if this has already been discussed, I started this thread because a friend of mine sent me the news article above.

[tszaboo]

Regular panels have issues with the temperature of them, because they get too hot in good weather, so if you concentrate, it needs cooling.
Which means moving parts.
Regular panels work quite well with diffused light and insulation. With this one it will scatter the light and it will not focus it anymore.
Regular solar panels are cheap, if you have to do anything with them, you end up with a more expensive system.
This is a solution looking for a problem. The idea is novel tough.

The next breakthrough will be quantum dots for solar.

[Marco]

Well obviously solar concentrators work, the problem is keeping the cost of the concentrator/tracker low enough that the march of progress on PV cost reduction doesn't cut you off before you're ready for market. A balloon in that respect has an advantage over rigid reflectors which require a ton more material, but the requirement for a tracker and inefficient area use would kill this. The cost of trackers and their racking didn't seem to be a significant cost disadvantage in 2008, but it is beginning to be one now. The cost of the active material was much higher in 2008 too. Time overtook them.

If utility scale solar has a future at all, it will be without tracking to begin with and even without rigid panels at all. Flexible PV with minimal also flexible mounting material (foamed plastic) is the future for utility scale solar. All that glass and steel are too much overhead, you need to absorb hail stone kinetic energy with (sectional) flexibility instead of massive amounts of glass, that's the road to cost reduction.

[Kleinstein]

The idea is not that bad. Concentrated PV can have a slightly higher efficiency, especially when using special cell made for higher intensity. The advantage is of cause no where near 400 times, more like 40% for the efficiency. This is however only with a clear sky and it needs additional tracking. 400 fold concentration is also too much to be practical for PV.

The question is if the concentrator and smaller, but higher performance cell can compete cost wise.  Some 20 years ago the math did not look so bad the concentrated PV, but with the dropping proces for the cells it gets increasingly difficult. It needs the tracking and usually water cooling as additional cost factors. The commercial classical cells also got quite a bit better - so AFAIK the advantage in efficiency got smaller in the last 20 years.

The problem I see with the ballon thing is the durability. Wind can be pretty harsh and the damage from UV is another point. The tracking part may also show mechanical wear and needs service.

[Twoflower]

There are several concepts using concentrator for PV systems. For example:Will we have a 20%-efficient (PTC) photovoltaic system?. Note that the date of that paper was 2001. At that time the PV cells where much more expensive compared to todays price tags. I think with the current PV-module prices and the problems such a system will have (you need tracking and probably thermal control). it will probably not enter mainstream use cases.