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| Guest |
 Posted: Tue Mar 22, 2005 1:01 pm |
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Before I get started, I'd just like everyone to know that I am not a
scientist or professor or whatnot. I am a 17-year old high school
student with an interest in physics and engineering, so if i say
something that doesn't make scientific sense, then don't attack me for
it. The reason that I ask is because i don't know to begin with.
Is there any real feisible way to increase the efficiency of a solar
panel? Because of the nature of solar energy, with the photons adding
energy to the electrons of a photoconductor to knock them out, isn't
the probability of a collison from a photon to an electron extremely
low? Is there any way to possibly contain the electrons within a region
that we can blast with light? Someone get back to me on this. |
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| Jumbyness |
| Posted: Tue Mar 22, 2005 1:14 pm |
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Guest
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<the1stlight@hotmail.com> wrote in message
news:1111514494.965539.274520@l41g2000cwc.googlegroups.com...
[quote:5a21069364]Before I get started, I'd just like everyone to know that I am not a
scientist or professor or whatnot. I am a 17-year old high school
student with an interest in physics and engineering, so if i say
something that doesn't make scientific sense, then don't attack me for
it. The reason that I ask is because i don't know to begin with.
Is there any real feisible way to increase the efficiency of a solar
panel? Because of the nature of solar energy, with the photons adding
energy to the electrons of a photoconductor to knock them out, isn't
the probability of a collison from a photon to an electron extremely
low? Is there any way to possibly contain the electrons within a region
that we can blast with light? Someone get back to me on this.
[/quote:5a21069364]
Google it.
Most has been done already, materials, thinning backside, dual materials,
focused light with cooling,
It is a efficiency vs. mfg. cost issue.
Tracking sun is big boost, can be done wo motors. |
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| Uncle Al |
| Posted: Tue Mar 22, 2005 2:42 pm |
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Guest
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the1stlight@hotmail.com wrote:
[quote:2f83582919]
Before I get started, I'd just like everyone to know that I am not a
scientist or professor or whatnot. I am a 17-year old high school
student with an interest in physics and engineering, so if i say
something that doesn't make scientific sense, then don't attack me for
it. The reason that I ask is because i don't know to begin with.
[/quote:2f83582919]
Boundary conditions noted. Look up "autodidact." Save the drama for
your mamma. Get down and push.
[quote:2f83582919]Is there any real feisible way to increase the efficiency of a solar
panel?
[/quote:2f83582919]
Thermodynamics proposes, kinetics disposes. One could go for input
intensity concentration (with or without imaging), exotic multi-layer
full spectrum absorbers, nano-scale fabrications to minimize losses at
every step... There is no reason to expect that any profitable
commercial solar cell fabrication will exceed 30% efficiency over the
working life of the product. Averaging 20% is truly fantastic. That
includes photoelectrochemical cells, photosynthesis (~1% efficient),
and everything else that pushes electrons from direct sunlight.
Solar cells are electricity generators of convenience or last resort.
You haven't accomplished anything until the energy necessary to
fabricate the thing is made up by generation. In many applications
this *never* happens, nor is it expected to happen.
[quote:2f83582919]Because of the nature of solar energy, with the photons adding
energy to the electrons of a photoconductor to knock them out, isn't
the probability of a collison from a photon to an electron extremely
low? Is there any way to possibly contain the electrons within a region
that we can blast with light? Someone get back to me on this.
[/quote:2f83582919]
If electron-hole production were 100% efficient it would not be of
significant incremental advantage. The photons' excess energy vs.
pair production comes off as heat anyway. You have to grab the pieces
before they can recombine. Wires do not generate solar energy. Dense
collector wiring leads to reduced output. Sparse collector wiring
leads to reduced output. Optimum collector wiring is not much of a
maximum.
Social advocate, "I will create a TV network wherein all programming
is moral and wholesome."
Pundit, "Almost nobody will watch it. How will you stay in business?"
Social advocate, "That is where the government comes in..."
Ground level solar input at high noon at the summer solstace at the
Equator under a clear sky is maybe 800 W/meter^2 across the entire
spectrum.
1) How many joules of energy at 100% efficency would accrue over an
hour?
2) What mass of gasoline over a square meter would need be burned to
release the same amount of energy? How deep is that layer?
HINT 1: The heat of combustion of real gasoline is about 43
megajoules/kg.
HINT 2: The energy needed to launch and insert a lump of coal into
low Earth orbit is its heat of combustion. You ain't gonna need much
gasoline in the foregoing example.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf |
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| Quantum Mirror |
| Posted: Wed Mar 23, 2005 11:16 am |
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Guest
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the1stli...@hotmail.com wrote:
[quote:361c0aa5d9]Before I get started, I'd just like everyone to know that I am not a
scientist or professor or whatnot. I am a 17-year old high school
student with an interest in physics and engineering, so if i say
something that doesn't make scientific sense, then don't attack me
for
it. The reason that I ask is because i don't know to begin with.
Is there any real feisible way to increase the efficiency of a solar
panel? Because of the nature of solar energy, with the photons adding
energy to the electrons of a photoconductor to knock them out, isn't
the probability of a collison from a photon to an electron extremely
low? Is there any way to possibly contain the electrons within a
region
that we can blast with light? Someone get back to me on this.
[/quote:361c0aa5d9]
Here are all the answers with a product that will come out in 2006.
http://www.nanosolar.com/index.html |
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