cone shaped solar array?

[tomy983]

Hi, I just noticed this on instructable
http://www.instructables.com/id/TRIPLE-YOUR-SOLAR-ARRAYS-OUTPUT/
I am wondering, since reading the comments the author doesn't look like is willing to do more testing, and I don't have any solar cells to give it a try mysel, what do you guyst think about it.. will the power output increase with this configuration given the same or even less area used for the array ?

[uncle_bob]

Hi

Nonsense.

Bob

[janoc]

That is a joke, right?

My BS meter didn't go off-scale, it spun around at least 3x ...

[The Soulman]

It even made my browser crash, cant believe what people claim to have invented. 

[Someone]

A lot of work went into improving the absorptance of solar cells (minimising the reflection of useful light) and micro texturing of the surface looked like this on a small scale, but there aren't big gains left to be made until cheap multi-junction devices arrive.

[m98]

Don't sign it off to quickly, I did a bit of concept design on a similar arrangement and got something like a 10% improvement over flat panels for directional light. Not that good, so i wasn't excited enough to actually build and test a prototype. But such a low angle as in the instructible could possibly only work with diffuse light, as solar cells drop off in efficiency as the angle to the light source gets smaller.

[uncle_bob]

Don't sign it off to quickly, I did a bit of concept design on a similar arrangement and got something like a 10% improvement over flat panels for directional light. Not that good, so i wasn't excited enough to actually build and test a prototype. But such a low angle as in the instructible could possibly only work with diffuse light, as solar cells drop off in efficiency as the angle to the light source gets smaller.

Hi

In the title he claims to improve the output by 300%. Later in the text he claims 670% improvement. That's not in any way the same thing as a 5 to 10% improvement.

Bob

[bitslice]

You'd boost output far more by surrounding the area in front of the panel with mirrors, the incident light has a significant effect

[uncle_bob]

You'd boost output far more by surrounding the area in front of the panel with mirrors, the incident light has a significant effect

Hi

... and then steering the mirrors to track the sun.

You also get a surprising boost by cleaning off the cells on a regular basis. Maybe a claim of 670% improvement for a windshield wiper ....

Bob

[rs20]

Let's just make sure we're on the same page. The instructables page is measuring power output per square inch of insolation/land area. This is clearly a bizarre measure to use, since the main cost of a solar panel array are the solar panels and wiring itself, not the "land area" (the roof is already free). But let's at least play along with this measure.

Don't sign it off to quickly, I did a bit of concept design on a similar arrangement and got something like a 10% improvement over flat panels for directional light.

A 10% improvement in what? Watts output per panel, or Watts output per area as defined on the instructables page?

I just want to make sure we're comparing apples with apples here, even though the instructables page is clearly pretty fraudulent (buying three times as many panels, packing them into the same space, and calling that "tripling your output" is not really giving credit to the money you spent on those extra panels...)

[uncle_bob]

Let's just make sure we're on the same page. The instructables page is measuring power output per square inch of insolation/land area. This is clearly a bizarre measure to use, since the main cost of a solar panel array are the solar panels and wiring itself, not the "land area" (the roof is already free). But let's at least play along with this measure.

Don't sign it off to quickly, I did a bit of concept design on a similar arrangement and got something like a 10% improvement over flat panels for directional light.

A 10% improvement in what? Watts output per panel, or Watts output per area as defined on the instructables page?

I just want to make sure we're comparing apples with apples here, even though the instructables page is clearly pretty fraudulent (buying three times as many panels, packing them into the same space, and calling that "tripling your output" is not really giving credit to the money you spent on those extra panels...)

Hi

Ok, I'll play along.

Both the "reference design" and the "proposed improvement" are fixed orientation arrays (no steering).

The "reference design" is set up to grab all the light at (on average) local solar maximum.

For the proposed improvement to do better, it has to do at least as well at max.

For the proposed improvement to do 3X better, it has to pick up *significant* power off of max.

*and / or*

pick up far more energy at max.

I see nothing in the proposal that will allow any of that to happen at the 300% improvement level. That assumes the above constraints are correct.

Now, if I deliberately mis-design the reference design by taking out 2/3 of the panels and then call it correct, yes, I can triple it's output by putting those panels back in the array. As a matter of fact, I can get 1,000% improvement by doing the same thing. I'm not doing anything at all on the "proposed improvement" side. All I'm doing is substituting a miss designed reference.

That's not the way it's done.

Bob

[tggzzz]

The TL;DR is that he's another ignoramus that doesn't know the difference between voltage and power.

The instructable states:

Light is a wave, a vibration with an energetic potential difference between points of positive and negative amplitude.
...
Sound, for instance, can be captured very efficiently. As a sound engineer for many years I have witnessed this for myself.

'nuff said. But then he goes on...

The first step is to wire our cells and according to the previous diagram we can fit two traditionally oriented 2x4" cells in an area of 4x4", and with the new orientation design presented here we can fit six 2x4" cells in a space of only 1.5x4".
...
We'll wire them up in series

6:2 = 3:1 so he will automatically get 3* the voltage. And guess what...

Next, mount your voltmeters and wire them accordingly. The meters serve for demonstration purposes

And that, ladies and gentlemen, is why professional publications have editorial control.

[Kleinstein]

It gets even better: with an ohmic load, 3 times the voltage gives 9 fold the power power.   

The one reason why the cone shaped form might get more power is because less light is lost by reflection. However this is less than 10% with modern cells. As a downside the intensity for the cells will be lower and this will reduce the efficiency (except for some thin film cells). Reducing the intensity be a factor of 3 will reduce efficiency be something like 5-10%. So more might be lost this way.

[System Error Message]

There is no such thing as a cone shaped solar panel, if it is coned shape than it is one of those water heaters that uses the sun to heat up and connect to a turbine.

solar panels are typically straight for cost reasons. Perhaps doing a comparison between curved and straight panels.

[tszaboo]

OK, maybe you might get more power if it is placed that way, but the author for that instructables is an idiot, who doesnt know what a photon is, and doesnt understand what is the difference between voltage and power. He has other instructables:
"Power your car with a FISSION REACTOR!"
"DIY Interferometer: Prove Einstein Wrong in 20 Minutes!"
"Free Energy from Thin Air!"

[System Error Message]

OK, maybe you might get more power if it is placed that way, but the author for that instructables is an idiot, who doesnt know what a photon is, and doesnt understand what is the difference between voltage and power. He has other instructables:
"Power your car with a FISSION REACTOR!"
"DIY Interferometer: Prove Einstein Wrong in 20 Minutes!"
"Free Energy from Thin Air!"

I remember reading about free energy from thin air, its not free energy from thin air, its more of using the emf around to power something small as we have many radio towers. It wasnt from instructables, it was from some book about being self sufficient, its only a trick and not free energy.

[uncle_bob]

There is no such thing as a cone shaped solar panel, if it is coned shape than it is one of those water heaters that uses the sun to heat up and connect to a turbine.

solar panels are typically straight for cost reasons. Perhaps doing a comparison between curved and straight panels.

Hi

The guy goes into it with drawings and descriptions. If there is a cone in there .... it's well hidden. If you make a cone shaped panel, it's a disaster unless you steer it. He never mentions steering. Even with steering the boost is in the "few percent to 10's percent" range. You do much better with a small panel and steered mirrors.

Bob

[Alex Eisenhut]

Ha! Humans believe in nonsense!