The last thing
I want to mention is some common issues that is, all of these
interim technologies, they have a similar way of making the module.
And they have a similar way of make the The contact of that.
So the module again, if you look from outside it looks like a big panel
of glass but of course that big panel of glass is not exactly one solar cell.
That would be really bad because it would have such a big electrode area.
And you lose a lot of your generated
electron and hold before you actually connect them.
So, what is done is that,
that big panel of glass is broken into
these individual cells which are connected in series.
From the outside it looks like this big shiny piece of glass.
But what you do is, you start with that big piece of glass, but then
when you deposit your first TCO material or
your first electrode, which is a conductive oxide.
It could be
either a zinc oxide or tin oxide.
Well once you deposit it, you patten into by using this laser scribe.
And then when you are done depositing your other
layer in, this gives this is a amorphous silicon cell.
So you again, you deposit your amorphous silicon, then deposit your back contact.
Then again you do a laser scribe.
So these are you know scribes of lasers which come and cut your cell.
And what it results in, it results in these individual blocks which are now
connected in series. So, here's another
picture showing the same cell. Even though from the outside it looks like
a big piece of glass, it's actually broken into these different small, small cells.
Which are then connected in series with each other.
So that you,
you know, you, from each of these cells
you are able to collect your carriers effectively.
And this is done by using this laser scribe
which is used to separate these layers into individual cells.
So this
This is how most of these modules
this is a first solar module. amorphous solar module that is even bigger
because it has the capability of making bigger amorphous silicon than.
from your display technology, because the same material which are used for the, the
same black, back links are the same tools that are used for, making these,
also.
[COUGH]
So, next time you know, you take, you see one of
these things on the roadside on a roof, you know, pay.
closer attention and, and 90% of the time you can
pretty much pin point the manufacturer just by looking at it.
in parallel you get Higher
so you get the first thing is, you want to get like a voltage you can easily
convert to ACI, so typically, wire, like, 36 of them.
Each has a VOC of between 0.6, 0.7, so
that gives you, like, 18, 20 volts in series.
And then,
these panels are then connected In parallel.
If you connect all of them in parallel, you'll still
get that same voltage you know, the USC of your
[INAUDIBLE]
set.
So they are combined and using your combination of series and parallel so on a
module level they're connected in series and then
these individual panels are then connected in parallel.
And you want to get to an optimum point.
So, for example, they are connected in series and
there's a, there's some dust, or there's some shading, right.
Or there's some leaves which fall on one.
So it will damage one panel.
So you want to have a, you typically have a bypass diode,
and that diode which prevents that, is on a panel level.
So, on a panel level, they're connected in series, and then they're
connected in parallel, so the last thing I want to cover is
is the, is the contacts. And, these are Called TCO that stands for
three letter acronym standing for transparent conducting oxides.
So the way you make these transparent electrodes is you then use metal oxides
either zinc oxide or or tin oxide or indium tin oxide and The
requirement you have on these is that you want these to be very low in
[INAUDIBLE]
distance, so that, you know, you don't have too much
loss or resistive loss, and you can collect all your carriers.
But, at the same time, you want them to be transparent throughout
the solar spectrum, and then you want them to be highly conductive.
And then, you want them, also people
want to use them as a light trapping material.
So they want to introduce morphology on this on this TCO material
such that it acts as a light trapping material as well.
And these are all conflicting requirement
because if, if something is transparent, that
typically means, you know, it doesn't have free carriers, so it means that It
should not have good conductivity but so you want it to be transparent over
the spectrum but still be good conductivity
so this, these are all conflicting requirements.
And typically when your resistivity increases
your decreases your transmitivity also decreases.
And the other thing people do with this TCO is that they texture
it and this is done very easily by dipping it in a, you know, a general
[UNKNOWN]
microstructures.
And these microstructures help in increasing this efficiency.
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