Name: 【TEDx】TEDxTucson - Dave Follette - Solar Energy At The Gigawatt Scale
Uploaded: 2014-03-31T01:49:58.000Z
Duration: 9 min 42 s
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Tonight, I want  to share with you a vision.

A vision to bring renewable solar energy  into each one of your homes,

and to make Arizona  an exporter of the same,

clean solar energy  to the rest of the nation.

So let’s start out  by talking about solar.

a picture kind of like this  comes to mind.

The sun is shining, it’s a blue sky,  maybe one cloud in the sky...

It’s just a beautiful picture  of renewable energy

with Tucson and Phoenix  kind of in that white circle right there.

And what you can see  is that we’re in the very center

of the best solar resource  in the country.

Right in the middle  of that red-orange zone.

So let’s put these two things together.

We’ve got clean, solar power,  and we’ve got the best solar resource.

just sprouting up everywhere,  all over the state?

Well, there are a couple of things  that solar has to overcome.

Right now, installed solar is about  50 % to 66 % subsidized

by the government  for every installation.

If you’re going to compete  with coal and nuclear,

somehow you have to get  beyond needing that subsidy.

in order to pay off  the capital cost of building it.

Now, a solar plant is going to  have to last just as long,

but it would be out in the desert,  dealing with monsoons,

dealing with the hot  Tucson summers for 20 years.

If you take a look  at this circle right here,

that’s about the area  you would have to cover in Arizona

And if you think about  solar panels right now,

that’s going to be  a lot of solar panels.

So whatever solution you use,  it has to be something

and make a real effect on the way  we use power in this country.

So that brings me to the very  basic problem of solar power:

that the sun is actually  a very diffuse source of energy.

and stand right in the center  of the solar power plant

for eight hours, twelve hours,  the whole day,

at the end of the day I’ll probably  have a sunburn, I might peel —

that might be  the worst thing that happens.

If I were to go to the center  of a coal or nuclear plant,

I would last maybe a second  before being incinerated,

and the difference there  is that in those plants,

and it’s much easier  to convert into electricity

So some of you may have already come up with a solution in your heads.

I’m sure many of you have  done this before in the backyard.

The solution therefore is to concentrate the sun.

And I’m sure many of you have had that experience concentrating the sun

it’s now much more easily  converted into electricity.

So this is the kind of experiment  you can do in your backyard.

But Roger Angel and the researchers  at the University of Arizona

So they took a 10–foot–diameter mirror, or segments of a mirror,

and focused that much sunlight  on a single point.

And instead of focusing  on a dry leaf or an insect,

they chose  a quarter–inch–thick plate of steel.

Within about 10 seconds, there was  a quarter–size hole in a plate of steel.

So that’s the power  of concentrated energy.

So now that we’ve solved  the problem of concentration,

now the problem is to convert that  concentrated energy into electricity.

And we’re actually fortunate  in the solar world

to have photovoltaic cells that are capable

of transforming sunlight  directly into electricity

this is a picture of some being installed on a roadway in Oregon —

And now this is a great technology,  but it’s fairly expensive right now.

And the reason that  two thirds of the price

is in the solar cells  is because sunlight is diffuse.

You have to cover a huge area  with these expensive semiconductors,

So let’s take  the concept of concentration

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【TEDx】TEDxTucson - Dave Follette - Solar Energy At The Gigawatt Scale

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