Maker Pro
Maker Pro

Would you like solar cells with various colours?

L

LU Wei

Jan 1, 1970
0
You may know that solar cells are generally blue and become black when
sealed in modules or panels. Would you like them in brown, gold, olive,
or purple? We are doing experiments on this recently and the first
results are good, esp. the gold cells are pretty with conversion
efficiency very close to normal blue cells.
Any comment is appreciated.
 
D

Doc O'Leary

Jan 1, 1970
0
LU Wei said:
You may know that solar cells are generally blue and become black when
sealed in modules or panels. Would you like them in brown, gold, olive,
or purple? We are doing experiments on this recently and the first
results are good, esp. the gold cells are pretty with conversion
efficiency very close to normal blue cells.
Any comment is appreciated.

In general, there is always a market for variation in style, so long as
the price point can meet the demand. I don't see why solar cells would
be any different. In particular, I would imagine there is a
military/outdoors market for olive/brown, especially if the process
allowed you to mix the colors/cells into a reasonable camouflage. Gold
does seem like it would have some upscale appeal for certain markets.
Purple probably wouldn't be different enough to command any significant
price premium. Seems like a tough nut to crack, though, because most
people seem to be mainly concerned about $/Watt.
 
L

LU Wei

Jan 1, 1970
0
Doc O'Leary wrote on 2009-7-10 23:23:
In general, there is always a market for variation in style, so long as
the price point can meet the demand. I don't see why solar cells would
be any different. In particular, I would imagine there is a
military/outdoors market for olive/brown, especially if the process
allowed you to mix the colors/cells into a reasonable camouflage. Gold
does seem like it would have some upscale appeal for certain markets.
Purple probably wouldn't be different enough to command any significant
price premium. Seems like a tough nut to crack, though, because most
people seem to be mainly concerned about $/Watt.
I can imagine those cells be preferred by those who have more decorative
concerns. Military usage is not practical because they are still very
distinctive in appearance. The cell colour are uniform. We think of
mixed colours on polysilicon cell but it's not implemented yet. The
$/Watt should not be a problem, because the manufacture cost is similar.
 
C

coj

Jan 1, 1970
0
LU said:
Doc O'Leary wrote on 2009-7-10 23:23:
I can imagine those cells be preferred by those who have more decorative
concerns. Military usage is not practical because they are still very
distinctive in appearance. The cell colour are uniform. We think of
mixed colours on polysilicon cell but it's not implemented yet. The
$/Watt should not be a problem, because the manufacture cost is similar.

Aren't solar cells optimised to their maximum efficiency which is
usually achieved with a blue colour on Si ?

The team at NaREC have been reporting this for a few years
http://www.narec.co.uk/img/18/pdfs/havemor_paper_valencia_version_2.pdf

For the thicker films you need to change the colour they'll need longer
in the deposition chamber (reducing throughput) and also be at lower
efficiency (the currents drop as you are increasing reflectivity) so I
would have thought the $/Wp would have to increase.
 
L

LU Wei

Jan 1, 1970
0
coj wrote on 2009-7-11 20:16:
Aren't solar cells optimised to their maximum efficiency which is
usually achieved with a blue colour on Si ? Yes.

The team at NaREC have been reporting this for a few years
http://www.narec.co.uk/img/18/pdfs/havemor_paper_valencia_version_2.pdf

For the thicker films you need to change the colour they'll need longer
in the deposition chamber (reducing throughput) and also be at lower
efficiency (the currents drop as you are increasing reflectivity) so I
would have thought the $/Wp would have to increase.
Here we must distinguish two different phases: cell and module. What we
have done is on the cell, throughput does decreased, though not much,
with efficiency reached 16.5%, which is close to our normal cells
(16.9%). At this phase so far so good, but when packed into module I
think the reflectivity problem will arise -- colour modules will
definitely reflect more light than black ones. Elaborate calculation and
design is needed to give a reasonable trade-off; and $/Wp would surely
increase, but we think some user may feel it worthy.
 
C

coj

Jan 1, 1970
0
LU said:
coj wrote on 2009-7-11 20:16:
Here we must distinguish two different phases: cell and module. What we
have done is on the cell, throughput does decreased, though not much,
with efficiency reached 16.5%, which is close to our normal cells
(16.9%). At this phase so far so good, but when packed into module I
think the reflectivity problem will arise -- colour modules will
definitely reflect more light than black ones. Elaborate calculation and
design is needed to give a reasonable trade-off; and $/Wp would surely
increase, but we think some user may feel it worthy.

If you've increased the reflectivity to change the colour of a cell then
it will lead to a drop in current in a cell and also a module. You might
get a slight encapsulation drop when laminating the module but you won't
get an extra reflectivity drop. Your new module power should be close to
the ratio of your cell efficiencies 16.5/16.9.
 
D

Doc O'Leary

Jan 1, 1970
0
LU Wei said:
Here we must distinguish two different phases: cell and module. What we
have done is on the cell, throughput does decreased, though not much,
with efficiency reached 16.5%, which is close to our normal cells
(16.9%). At this phase so far so good, but when packed into module I
think the reflectivity problem will arise -- colour modules will
definitely reflect more light than black ones. Elaborate calculation and
design is needed to give a reasonable trade-off; and $/Wp would surely
increase, but we think some user may feel it worthy.

Keep in mind that there is even potential to use the reflected light for
solar thermal in a hybrid system. If it's not diffuse reflection, I
could easily see making a fresnel mirror out of gold panels. Heck, it
might even be worth more significant drops in PV efficiency if you could
put out silver panels!
 
L

LU Wei

Jan 1, 1970
0
coj wrote on 2009-7-14 16:07:
If you've increased the reflectivity to change the colour of a cell then
it will lead to a drop in current in a cell and also a module. You might
get a slight encapsulation drop when laminating the module but you won't
get an extra reflectivity drop. Your new module power should be close to
the ratio of your cell efficiencies 16.5/16.9.
It will not be the case because there is a match problem between the SiN
coating and laminate coating. The reflectivity ratio of gold and blue
cell may be 16.5/16.9 (if we omit other factors), but the reflectivity
ratio of gold and black module will surely be less than that.
 
L

LU Wei

Jan 1, 1970
0
Doc O'Leary wrote on 2009-7-15 0:20:
Keep in mind that there is even potential to use the reflected light for
solar thermal in a hybrid system. If it's not diffuse reflection, I
could easily see making a fresnel mirror out of gold panels. Heck, it
might even be worth more significant drops in PV efficiency if you could
put out silver panels!
Your suggestion of hybrid system is valuable yet I think we still have
no R&D ability and investment in this area. Anyway, silver panel is not
practical -- it will reflect too much light!
 
L

LU Wei

Jan 1, 1970
0
LU Wei wrote on 2009-7-15 11:19:
It will not be the case because there is a match problem between the
SiN coating and laminate coating. The reflectivity ratio of gold and
blue cell may be 16.5/16.9 (if we omit other factors),

Sorry for my mistake: the reflectivity ratio should be 16.5/16.9 +
(1-16.5/16.9)/0.05 ~= 1.45 (if we let the reflectivity of blue cell to
be 5%);
but the reflectivity ratio of gold and black module will surely be
less than that.
And the reflectivity ratio of gold and black module will surely be
higher than that (greater than 1, anyway).
 
L

LU Wei

Jan 1, 1970
0
louis4sun wrote on 2009-7-14 16:14:
Hi Lu
We are interested in "Gold" color for our next EcoMarathonShell Solar
vehicle
Thatcould promote your company
I send to you a PM
Regards
Louis
Maybe it will be an opportunity for both of us. I have noticed that your
message is from Google groups; I am afraid your PM cannot reach me by
"reply to author" link on Google's web interface. It's a custom on
Usenet not to use valid email in "From:" header, but in "Reply-To:"
header. With a normal newsreader there should be no problem to reply to
me privately, but it seems Google groups has not been aware of this.
Please reply to luweitest {AT} gmail.com instead.
 
J

Jean Marc

Jan 1, 1970
0
LU Wei said:
You may know that solar cells are generally blue and become black when
sealed in modules or panels. Would you like them in brown, gold, olive,

I think there must be a market around historical value places or "sight
protected" areas where I live, near chateaux, and such. For red - tile color
panels that look just like an old-time roof.
 
L

LU Wei

Jan 1, 1970
0
Jean Marc wrote on 2009-7-17 14:46:
I think there must be a market around historical value places or "sight
protected" areas where I live, near chateaux, and such. For red - tile color
panels that look just like an old-time roof.
Our market personnel will bring some cells (or modules, if we are quick
enough) to an expo in America this year I think. Maybe there will be
some opportunities.
 
E

Eeyore

Jan 1, 1970
0
LU said:
You may know that solar cells are generally blue and become black when
sealed in modules or panels. Would you like them in brown, gold, olive,
or purple? We are doing experiments on this recently and the first
results are good, esp. the gold cells are pretty with conversion
efficiency very close to normal blue cells.
Any comment is appreciated.

I suppose they might look pretty !

A way to increase conversion efficiency inexpensively would be more useful
all round though.

Graham
 
M

Mel

Jan 1, 1970
0
LU Wei a écrit :
You may know that solar cells are generally blue and become black when
sealed in modules or panels. Would you like them in brown, gold, olive,
or purple? We are doing experiments on this recently and the first
results are good, esp. the gold cells are pretty with conversion
efficiency very close to normal blue cells.
Any comment is appreciated.

There is a potential niche market for building integrated applications,
especially if you can get something in a reddish colour.

Red terracotta (fired clay) tile roofs are common across Southern
Europe, where there is also a high percentage of national and world
heritage listed sites. A reddish modules, on a similar coloured backing
film could have a potentially large market, even if the final product
has polycrystalline module efficiencies at monocrystalline costs.

France and Italy both have attractive feed in tariffs, it's worth
discussion with distributors & developers in those countries.


Regards
Mel
 
Top