So today, we're looking at solar resources.
As part of the overall energy resources we have available to us.
And today, we're going to look at the interactive map, how to create maps to
find out exactly how much radiation and solar energy is available to us.
To utilize to meet some of the energy needs.
It's a little bit difficult thing to calculate because there's so many
variables that the amount of radiation depends on it.
It depends on where you're located on a map.
What latitude, longitude you're located, both from altitude makes a difference
time of year makes a difference panel, panel mounting and orientation of that
mounting makes a difference. Two axis tracking always facing the sun
is the best. We can, excuse me, we can fix the panel, which is the cheapest way
to install them and tilt them up toward the equator at a fixed angle.
That means if we're in the up northern hemisphere we're, we're tilting them up
to the south pole. If we're in the southern hemisphere we're
tilting them, them up from the horiz, from the flat horizontal surface toward
the north pole. And we can also have fixed horizontal
mounting, flat on the ground, or we can vertical mounts, on the sides
of buildings. Again, just to remind us, what we saw
last time, this is what we're talking about here.
And the tilt angle that we're talking about is this one right here.
This is the tilt angle that we refer to. And this, this diagram is written for the
northern hemisphere. Because it talks about tilting it to the
south. And you only want to, that's going to
hurt you, if in the southern atmosphere, and you tilt it to the south.
So, but it's, it's real, it's, Drawn for the northern hemisphere, of US
centric, in other words because it's done by the National Renewable Lab of the US
Department of Energy. So we can refer back to that if we get
confused about some of these choices that we're going to make.
Now, we're going to Use and interact the map that they have,
interact the website. It produces a map such as this and to
show you what we're going to get and each 1 of these dots on this map, by the way,
represents an experimental Data point. In other words they have solar radiation
at all of these points. And they use that to correlate the
correlate the data, and so the map corresponds to that.
And the, this is the scale that tells us what the colors represent.
In other words, this yellow, of course, means that, that on an annual basis, this
one is done on an annual basis Creates 5 to 6 kilowatt hours per square meter per
day. And, in this area, it's the light green.
So it's 4 to 5 kilowatt hours per square meter per day.
But now, that's not. Every day, obviously, is not going to be
that. Winter's going to be less than different
in summer. But, on a average basis,
cloudy days will be less than sunshiny days, but on an annual average basis,
that's how much solar energy will, strike a square meter, about 10 square feet, on
a daily basis. A kilowatt hour is 3,413 BTU's per hour,
if you want to convert that. So that's what we're going to create
here, and another example This one is the last one.
This one is, as I mentioned, is the tilt angle is tilted up to the south and the
Northern Hemisphere of the U.S. at the latitude at an annual basis.
The next one shows it for a two-axis tracking situation, where we're always
facing the panel toward the sun. And we're looking at the best month, so I
took the best situation here. And you can see that from the scale that
we're receiving a lot more energy in July.
And if we want to pay for the extra cost of the two-axis tracking mechanism,
we will prob-, have a lot more energy striking our collector that we can
hopefully convert to something useful. And all in the South, you can see, it's
it's around 7 to 8 KW hours per square meter per day.
So you can do your trade off and determine if it's worth your while to
pay for a 2 axis tracking system. but you, things are much more uniform
across the country if you do a 2 axis tracking situation, as you can see here.
Out here, and even in the Northwest, you're out there at the high point of 10
to 14 kilowatt hours per square meter per day.
Those are the maps that we're going to create here.
And we do that by for, using an interactive on-line map and this is the,
this is the link right here. Whoop.
Get it in a minute. this is the link and I think if you click
on it we'll have it come up. Okay, when we go to that link that's on
that slide, this is where Were directed to, and, as you can see here, we have
several choices that we need to make. We need to select a data type.
Do we want the average, the minimum case or the best case? the next we can choose
the month, what month that we're interested in, or
we can choose the annual average, which is, usually I pick, but let's see.
Here we go. what's clicked here is January.
And what I've showed you before is the annual average for all of these months
for the entire year. And I, the first map that I showed you
was for flat plate down here, tilted south at latitude, tilted south at
latitude. So we go down, and we click view map to
see what it looks like. And this is the map that I showed you
before and that I've already had run. So you can create your own situation.
If we go back, decree the 2nd map that I mentioned, we can look at July, and July
rather than the annual average, which is the best month.
We could also look at some of the worst months, being say to January, if we like,
and Look at the single axis, not single axis, but two axis tracking, flat plate.
Now let me just mention here, it's got 2 choices.
Two axis tracking concentrator, and two axis tracking flat plate.
The reason there's a difference, is because a concentrator will only reflect
and concentrate at the point you wanted, the direct radiation coming directly from
the sun. There's some diffuse radiation that's
coming from the atmosphere that gets, scattered as the sun is coming through
the atmosphere. Which is so there is less energy coming
as direct radiation that a concentrator can deal with than if it's a flat plate.
So if it's a, it's, that's the reason there's a difference there, but there is
a difference between a concentrator and a flat plate.
Here, we're talking about a flat plate is what I've been talking about.
So that's the, I created the, the high side where, that had all the red on it,
using a 2-axis tracking flat plate and looking at the one month of July.
And if I look, click view map, I come up with the map that I showed you before,
where it's more uniform across the country, much higher radiation intensity
per unit area, with the scale down here shown.
It goes from 10-14 out here in the West down to the tan which is about 7 to 8,
over here all up and down the east. So there's some real advatages to being
tracking and of course being in July. We can look at that, this looks real
quickly at what it looks for Annual average, if we do 2-axis tracking, we go
back and Return to Menu, and we'll go down, and we look at Annual average,
rather than just, just July, that we just looked at and we'll do the 2-axis
tracking. To access flat plate again, the only
thing I've changed from the previous case was annual rather than July.
And in that case you can see that the annual average is.
Significantly higher out here in the south west.
So there's some real differences in the characteristics of the amount of
radiation that's available to you depending on where you're located.
So that the interacting map for the US and I hope you find it beneficial.
And, by the way, if you click a, a PDF version That, up there at the top, it
will create a a, before you go, got some software problems on that.
But you can down, you can show it as a .PDF and download it and it's a little
clear, cleaner picture. But that, that completes the interactive
solar map that shows you how to determine how much solar energy is available to us
in different situations in the U.S. at least.
And there are means to do that also any place in the world.
Okay, thank you.