Table 6 D4 discussion excerpt; 16:03 to 20:29

Facilitator

1

One of the questions that I had—and this builds on something that you said as well—is a hot state really the ideal place? Because they talk about a number of negative factors, particularly temperature ((multiple participants nod))…

Barrett

2

I had the same question. ((points to notebook, laughs))

Facilitator

3

[well, great, why don’t you ask your question?]

Fran

4

[I do too.]

Georgia

5

Yeah, I was gonna bring that up. Go ahead

Barrett

6

That's funny

Facilitator

7

Would you like to phrase the question?

Barrett

8

So I read and learned that solar cells run efficiently at 25 degrees Celsius. Obviously, that doesn’t really [inaudible crosstalk]…

Fran

9

[Inaudible crosstalk] which, is that room temperature basically?

Georgia

10

[It’s like 77.]

Multiple

11

[Yeah.]

Barrett

12

So basically, it was just like what problems does that face in a hot state? How does that affect them?

Fran

13

Or how is it combatted, right? How do we combat that?

Georgia

14

[Or do they?]

Dakota

15

[A cooler city] would be perfect

Georgia

16

Because he was saying on our tour—so connecting our tour to that—he was saying the spike is, or their optimal collection is, only three months. So, do they combat it? Is there a [inaudible] down there to even further work with the high temperatures? EE

Cat

17

And also on the tour, they were talking about how shading the area has convection and cooler -cools the bottom of the panels, which actually cools the panels themselves, so they produce their own shade and cooling system. Which is cool. EE

Barrett

18

Is that only for the shaded ones? Like what about the roof ones?

Cat

19

The roof ones don’t have room for that convection. So,

Fran

20

Wait, which ones were shaded? [Where did we see-]

Alex

21

[Under] by that building

Georgia

22

Yeah, where we were standing under the [trees and everything]

Cat

23

[The walkways.]

Alex

24

Yeah, because he said, there’s a breeze that’s created from that canopy, basically

Fran

25

So the cells were up here, exposed to full sun

Georgia

26

Yeah, and then there’s some that were strategically missing, because that’s what we said when we first saw one of them, like, why are there so many missing? And I couldn’t hear him when the buses were up there. When we could hear he said that this was purposeful

Alex

27

Yeah, so they’re doing, he said, if you missed part of it, they’re doing a research project to see what kind of plants grow underground with that when they create sun shading. But then also it, like a bonus; it creates that current that cools the underneath. I was doing a lot of Googling about what people are doing. And it’s, um, there’s research now to do like misting fans set up somewhere underneath the panel. So I’m guessing it would be like a tiny spray or whatever you know, to kind of keep it cool? Cause it does lose like a about a percent or two efficiency with every five degree Celsius jump. EE

Cat

28

Which is, like, 60

Ed

29

There’s another type of solar, um, I guess it’s not a panel, but it’s a thermal solar collector and it’s concave. And they have farms for that, too, in some of the more higher temperature areas. So where it’s very hot, they can just switch out and use those others which are much more efficient during the hotter periods or places. And what they do is they basically just have conduit pipe at the foci of the concave shape and those are mirrors, and the temperature of that water can get up to and exceed 750 degrees, which then they would use to produce steam, and then to mechanical energy, then to electricity. EE

Fran

30

I was wondering about that

Alex

31

Oh, cool

Cat

32

So we could have a combination there so you can have solar panels during the cooler months and those during the hotter months and get the most efficiency out of all

Ed

33

Sure, you can put one underneath the other, and then when the time comes, you just—it just rotates

Dakota

34

You need to patent that

Ed

35

Because you’d probably also, there’s a tracking system, so those actually will rotate on a horizontal axis to maintain the optimum angle of incident, you know, towards the sun. And then, of course, the panel would do the same thing, when it’s the primary. EE

Alex

36

That’s cool