Welcome to the Solar Collector
Brainstorming and Development Page!


 

Home

Hot Air Collector

Hot Water Project 1

Hot Water & Space Heating

Solar Electric

Solar Construction 101

FAQs

Best Collectors

Simply Solar
Register Calendar Latest Topics
 
 
 


Reply
  Author   Comment   Page 1 of 2      1   2   Next
RevI

Registered:
Posts: 48
Reply with quote  #1 

As per this video above, Australian scientists have created a new, highly efficient (46%) solar panel first by using multiple layers of panels producing energy from different wavelength and by reflecting the rest of light into another solar panel. That simply means that light reflected from solar panels are high enough.

stmbtwle

Avatar / Picture

Registered:
Posts: 2,748
Reply with quote  #2 
Sure why not?

Casual tests I ran a few weeks ago with a radiance meter seemed to indicate the reflection off a pv panel with a glass face set at 90% to the sun was around 20%. What part of this was from the solar cells, the white backing, or the glass I don't know, and I'm not going to spend the time and money to find out,

As the angle between the panel and the sun became more oblique, the amount reflected increased, the same as it does off a piece of glass or the surface of water.

Incidentally, the reflection from the PV panels was LESS than the reflection from the twinwall-covered thermal collector next to them.

Two panels oriented in a "vee" formation could reflect the light into each other and might increase the total capture, or panels with clear rather than opaque backs might capture light from other panels. This might be the idea behind the "solar tree". However as each panel would have to be mounted at an angle to the sun, it might be less, too. Since the sun "moves", to optimize reflections and minimize shading a tracking device might also be required. All this hardware and paraphernalia might increase total efficiency but it would also increase cost.

Tracking mounts have been around for a long time, but in many cases they've fallen out of favor simply because of cost. There IS one large tracking array near me (several acres), but it only tracks from east to west and makes no adjustment for declination.

While it may in theory be possible to invent a better mousetrap (mount), in the end COST "efficiency" is what usually matters.

KISS!


__________________
Solar is like the wind. It may be free, but putting it to work isn't!
Willie, Tampa Bay
RevI

Registered:
Posts: 48
Reply with quote  #3 
As far as I know, glass panels are used to reduce the reflection from solar cells.
stmbtwle

Avatar / Picture

Registered:
Posts: 2,748
Reply with quote  #4 
Personally I think the glass is just a necessary evil to protect them from the elements. Solar cells are pretty fragile and the connections subject to corrosion.

You could always build two solar panels, one with and one without glass, and determine which one works better.

__________________
Solar is like the wind. It may be free, but putting it to work isn't!
Willie, Tampa Bay
RevI

Registered:
Posts: 48
Reply with quote  #5 
Maybe. But the main reason behind using glasses is to reduce the glare from the solar cell. Kindly read this article.
stmbtwle

Avatar / Picture

Registered:
Posts: 2,748
Reply with quote  #6 
So? That's the coating, not the glass.

The same article states that "Each glass surface reflects about four per cent of the incident light, representing a significant loss of light into the module."

You have just contradicted yourself. Why not put the coating directly on the solar cells and eliminate the glass? You would save money. I stand by my argument.

Anti reflective coatings have been around a LONG time.

Ultimately, it's all about the money. Where is the cost/benefit analysis?

__________________
Solar is like the wind. It may be free, but putting it to work isn't!
Willie, Tampa Bay
RevI

Registered:
Posts: 48
Reply with quote  #7 
Quote:
Originally Posted by stmbtwle
So? That's the coating, not the glass. The same article states that "Each glass surface reflects about four per cent of the incident light, representing a significant loss of light into the module."

Question is, what would be the amount of reflection without the glass. I hope we both agree that 4% isn't a big number.
stmbtwle

Avatar / Picture

Registered:
Posts: 2,748
Reply with quote  #8 
I'm sure it depends on the glass, and the angle of incidence.  I guess you'll have to do some tests and find out.  Please post the results for the rest of us.
__________________
Solar is like the wind. It may be free, but putting it to work isn't!
Willie, Tampa Bay
RevI

Registered:
Posts: 48
Reply with quote  #9 
I am sure that such tests have already been conducted. Therefore, before investing my time and money into it, I want to be assured that such things have never been experimented yet.
stmbtwle

Avatar / Picture

Registered:
Posts: 2,748
Reply with quote  #10 
If they had been, I'm sure you would know about it already.
__________________
Solar is like the wind. It may be free, but putting it to work isn't!
Willie, Tampa Bay
Previous Topic | Next Topic
Print
Reply

Quick Navigation:

Easily create a Forum Website with Website Toolbox.

 

web statistics