Hello folks. Welcome to the screencast.
So, I have some very exciting news to share with you guys.
So I've decided to go solar, and install some sort of panels on my house.
And the dilemma that I'm immediately faced with is to which roof of, or, you know,
which surface among these four different roofs should I install my solar panel on?
So assuming I have this nice big house which has this
multi hatcheted roof. And let's say this, this
part is is facing the south, so this is my south facing part.
And opposite side of this would be my my north facing part.
Similarly, this part of my roof is what is facing
the west, and this part is what is facing the east.
So, you know, out of this four possible
choices, where should I install my solar panel?
And the answer really depends upon, where do I live?
And let me illustrate why.
So I'm, I'm currently living here in the northern hemisphere.
And you know, Bay Area, it has a latitude of approximately approximately 37 degrees.
So now
if I'm, if I'm living in the northern hemisphere, and my
house, just for, you know, the purpose of is located like this.
So what I want now to do is,
I want to have this panel essentially facing the sun.
So I have my sun located somewhere over here.
And then I have these photons, or this
light, coming from the sun in this particular direction.
So now, what I want to do, is to, to optimize the efficiency of my panels.
I want to essentially, you know, have this panel
facing toward my panel, which is located over here.
This should be facing the sun.
So this will happen if I'm located in the Northern Hemisphere.
Then I should place my panel on the south-facing part of my roof.
Similarly if I'm located in the Southern Hemisphere, I should place my panel
on the north-facing part of my roof.
And the optimal angle at which this roof, or I believe this
panel must be tilted, is essentially equal to the latitude of this place.
I have proved that, that this panel, in fact facing the sun
whenever I choose, I tell this through certain angle of of the latitude.
Let me illustrate
this folder, so there's no confusion.
So let's say I'm at a altitude of theta, and then this is,
this is essentially my my direction of my roof if I have north there.
So this is my house, and if I have north there, then this is the direction.
Now if I tell this in folder a angle of
theta, so my panel is essentially facing this particular direction.
And if I choose this to be theta as well, and this angle to be 90 degrees, right?
And if I have this angle to be theta, then this angle would be 90 minus theta.
So, if I connect this line over here, then if I
look at this bigger triangle, this bigger triangle A, B, C.
So, now I can see that this angle is theta,
and this angle is 90 minus theta.
So, this angle essentially now must be 90 degrees.
While this panel is facing this direction of
the incoming sunlight or the radiation from the sun.
So that's why that it makes sense to essentially orient your roof, or
the angle of your this of this tilt should be theta as well.
And as you can see, this is facing the South.
If I'm in the
in the, in the Northern hemisphere, similarly, if this house was
located over here, then I would choose the opposite opposite roof.
So I, I would choose essentially the not facing part of my roof.
So, now the optimal direction as I just It's equal to the latitude.
So, if I'm living in the Bay area, the latitude is 37 degrees.
So this optimal tilt would be 37 degrees
and I'll choose a South-facing part of the roof.
But many times you know, you, you can't choose really the angle of your, the roof.
Unless you're designing a new house.
So let's say you are buying an old house.
And it has maybe a higher angle. Or it has a lower angle over here.
So you can still get around that.
So you still, if you're living in the Bay Area.
Which is the Northern hemisphere.
You choose again the south-facing facing part of the roof.
And if we are at a higher angle, you can add a fixture over here,
so that your solar panel is placed in this particular manner, so that this angle is,
again, equal to the latitude, which is 37 degrees.
Similarly, if you have lower tilt on your roof, you can add a
fixture over here before placing the panel and still get that optimal angle.
This will of course add this fixture this
fixture will add to the cost of your panel.
But we'll, discuss that later.
If you, if you get lost here, if you lose your GPS, and you need to find directions.
A good way to would look at that if to look at the nearby
houses, and if they happen to have if they happen to have solar panels installed.
Then you can look at you know, which side or, the,
roof which is essentially on which the solar panels are installed
should be the South facing direction.
So if you get glass, this should be essentially be the South facing diretion.
And if you got even lost, you know, you, you are flying somewhere and you had a
plane crash, you know something similar to what happened
in Lost and you wake up in a dessert.
With these solar panels, you'll figure out, these solar panels they are at a
fixed angle, and you want to figure out how far you are from the equator.
Look at the delta of these solo panels
and that should essentially give you the patterns.
Hopefully people have installed these patterns in the right way.
So this is assuming this optimal optimal tilt
is assuming that I have the sun shining perpendicular.
I have, you know, I'm at the noontime
where the sun is exactly shining at the top.
But in reality the sun, if you're, if I'm located on Earth The sun
will essentially rise it would rise in the east and set in the west.
So there's a direction of motion associated with that.
Another thing which we should need to take into account, which makes this even
more complex, is that the Earth is tilted with respect to its axis of rotation.
So we. I know that Earth
is essentially tilted at an angle approximately 23
degree with respect to it's axis of rotation.
So let's it had a point in the northern hemisphere.
So when it's during the summer time and it's summer solstice.
So this angle at which my panel should now face towards the sun is now reduced.
Similarly when I go into, it's reduced by this angle of
the tilt.
So if essentially and I was at latitude of theta, so
this angle, now the optimal angle, is actually theta minus my tilt angle.
And if I go in the winter, then its optimal angle is
theta plus 23 which is adding this adding this angle to the tilt.
So now that we have discussed the phenomenon for day and
night, and tilt
[INAUDIBLE].
It's a good it's a good point to introduce the need of the tracking.
And to introduce the need of the tracking, what we can do is look or think
from the prospective of these mere mortals or
our, human beings who are living on the.
On the planet. And for us, this is how all
these interplanetary motions manifest
into how do we perceive the sun.
So every day, the sun essentially goes around.
Or, actually, the earth is going around, but,
looking from the perspective of these mere mortals The
sun is going around, so our panel needs to track this motion of the sun every day.
And then I have this fixed I have this optimal angle, which corresponds to
the latitude.
In this case it's a latitude of 55 degrees.
But this only occurs during the months of the equinox, so this would be the months
of March And September if I'm if I'm living in the Northern Hemisphere.
Then during the Summer that's in the month
of June, if I'm in the Northern Hemisphere.
I'll see the optimal angle to be
reduced by the angle of the, by the tilt of the earth.
Which is 23 degrees.
And if I go in the winter, then I see my sun is essentially, you know, it's rising
at at much higher tilt and I, I have
this tilt angle to be added by this optimum angle.
Which needs to taken to account as additional.
Angle coming in from the tilt of the arc.
So that is why if you design optimal
tracker system, you often track these two axis.
So you track the motion of the, of the sun every day so that's one axis for that.
And the other one is to track the tilt of
the Earth, so this axis tracks the tilt of the Earth.