nano coatings?

System

Saw an engineered coating that can be applied to any solar panel that will increase efficiency by 90%.

Evidently, the nano coating reflects light in every direction which increases efficiency even if the sun is not directly above the panel.

anyone hear anymore about this technology? I heard about it on natgio, planet green, or discovery. i can't remember. I watch these channels daily.

System2

Re: nano coatings?

also heard about a guy developing a lense that goes above the panel. concentrates more energy on the panel like a kid burning ants with a magnified glass.

BB.

Re: nano coatings?

Those are all "true" in the sense that for various conditions (off-angle sun, reducing the use of expensive silicon solar cells by using a concentrator lens/mirror) can work.

The actual real world results are that they are usually, too expensive, don't last, cause other issues like over heating, short life, or require 1 or 2 axis trackers to keep lenses focused on the cell...

The old 80/20 rule... You can get 80% of something with only 20% of the work/expense--to get the last 20%, you need to spend 4x as much work/money. Frequently, just not worth it.

-Bill

System2

Re: nano coatings?

BB. wrote: »

Those are all "true" in the sense that for various conditions (off-angle sun, reducing the use of expensive silicon solar cells by using a concentrator lens/mirror) can work.

The actual real world results are that they are usually, too expensive, don't last, cause other issues like over heating, short life, or require 1 or 2 axis trackers to keep lenses focused on the cell...

The old 80/20 rule... You can get 80% of something with only 20% of the work/expense--to get the last 20%, you need to spend 4x as much work/money. Frequently, just not worth it.

-Bill

very true on the lense, but the nano coating doesn't magnify the light at all, just gives light from every angle.

any are most home systems single silicon or multiple silicon?> Thanks.

dwh

Re: nano coatings?

BB. wrote: »

The old 80/20 rule... You can get 80% of something with only 20% of the work/expense--to get the last 20%, you need to spend 4x as much work/money. Frequently, just not worth it.

-Bill

I prefer Sturgeon's Laws:

http://en.wikipedia.org/wiki/Sturgeon%27s_Law

In this case, both apply.


And to the OP (non-fiction, available to read online for free):

http://www.wilmccarthy.com/hm.htm

dwh

Re: nano coatings?

Old School wrote: »

also heard about a guy developing a lense that goes above the panel. concentrates more energy on the panel like a kid burning ants with a magnified glass.

It's called a fresnel lens. And it's been done many times already.

http://www.google.com/search?q=fresnel+lens+solar&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

BB.

Re: nano coatings?

Old School wrote: »

very true on the lense, but the nano coating doesn't magnify the light at all, just gives light from every angle.

I was speaking towards your first point about nano-coatings... Typically, those are applied to reduce reflection when the panel is not pointing straight at the sun. Anti refective coatings would probably have less effect on tracking panels. And, because when the sun is dramatically off angle (morning/evening) the you run into the fact that the sine of the angle to the sun reduces the effective area of the array (an array pointing off at 45 degrees has a sine(90)=0.707 (or 1/sqrt(2) and their is more "atmosphere"--so less energy available at ground level)--that nano coatings can only increase solar collect probably by a hand full of percent or so... Add that if it is the glass panel that has the anti-reflective coating--that means that soap and water must be taken to the panel every few weeks to preserve the surface finish).

Anyway--I am not sure which technology you are referring to--But, in general, most will not significantly change the cost curve at all vs standard solar panels used today. Manufacturing cost improvements are right now reducing costs per kW much more than these other technologies.

any are most home systems single silicon or multiple silicon?

Not quite sure I understand your question--There are Mono-Crystalline and Poly-Crystalline silicon PV cells--and amorphous silicon cells too...

Mono-Crystalline are large ingots of silicon that have been grown as a single crystal. When cut into solar cells--the surface is an even black color (one crystal arrangement).

Poly-Crystalline solar ingots have multiple crystal orientations. When cut into cells, they have that "shattered glass look".

Operationally, Mono-Crystalline panels (typically) cost a bit more to make and are a few percentage points more efficient. So, the vendor can demand more from the customer as for space limited applications (such as a small roof)--you can get a bit more power out of the same sq. ft. of solar panels vs Poly Crystalline.

Other than the above--the two are virtually identical in overall performance and longevity.

Amorphous panels don't grow crystals but spread a finely ground silicon mix down on a metal substrate. Can be much cheaper to manufacture. However, there is a significant drop in power output in the first 6 months of sunlight (~20%) and the panels are almost 2x the surface area as crystalline solar panels (more square footage for same amount of power).

Also, many "cheap" panels are made from Amorphous silicon -- and the average life time can be less too.

Anyway, the above is roughly accurate--But as always with generalizations, there are exceptions.

-Bill