Could Enough PV Significantly Cool the Desert?

Ok, you are a babbling clown with cartoon ideas.

Are you aware that the Sun moves during the day?

No, I am asking you what are you going to use to make this magic filter?

Arm waving about gratings is not an answer.

So you are admitting you are too stoopid to use reflectors so that PV panels may be oriented in any direction??

Bret Cahill

The price of solar PV is dropping so fast soon no one will bother with tracking mechanisms and other nonsense unless land is at such a premium they need dual use of the sun:

Red light for crops and green light for solar PV.

The arguments for dual use aren't complicated:

1. Most solar energy is green and useless to crops. Why not use it for PV?
2. Plants won't grow in the summer desert sun. Crops only grow in the winter when there is _less light_, 30% shorter days, etc. Why not extend the growing season into the summer by sending unwanted solar energy to PV?
3. The same goes for PV as for plants. Why not keep the PV cool by sending the excess solar to the plants?

Using green light for solar PV is green in more ways than one.

Bret Cahill

So what is the sin theta loss of a panel facing 45 degrees to the horizontal _downward_ receiving green light that has been reflected or refracted upward 45 degrees with the horizontal?

Are you aware that trackers can follow the sun during the day?

No answer?

They are already doing it with grating.

Are you too stoopid to google or what?

Who give a s*it?

The cost of all the required machinery to do this would be so high the scheme is guaranteed to lose money no matter what.

Yeah, keep telling yourself that.

You forget the blue-violet also needed by green plants.

Just cartoonish.

You mean other than the enormous cost of all that machinery?

Plants grow just fine in the summer desert sun of the San Joaquin Valley.

Of course, there is a HUGE system to get the needed water there.

Nope, that you are too childish to understand the huge cost of all that machinery to grow crops where there is no water in the first place or there would already be crops there.

Everywhere the Sun is in the sky and not in the ground.

"You are vexed therefore I am right about you."

-- Nietzsche

OK, then show how it's possible.

Well? Where are they?

Since you won't let it go...

The best of mirrors reflect about 90% when they are nice and clean.

If you have two relflecting surfaces, you have .9 X .9 X .707 X .707, so you wind up losing 59.5% of the energy from this scheme assuming the panel is normal to the last reflector.

If the panel is at an angle, multiply .405 by the sine of that angle and that is what you would have left.

In reality the mirrors will get dirty so they are going to reflect a lot less than 90% once the system has been in place a day or two.

Why?

It may be possible, but it is highly impractical because of all the sin (theta) and reflection losses plus the cost of all the tracking mechanisms required to get anything at all out of it.

Then there is the issue of you are attempting to minimize shadowing by putting up 2 to 3 times the area of "stuff" to create shadows.

And lastly there is the issue of there being no water in the first place or there would already be crops growing.

Everywhere the Sun is in the sky and not in the ground.

My diagonal mirror has reflectivity is above 99% over the entire 4000 to 7000 Å photo-visual range, jimp.

How profound!

The unstated and obvious condition is that we are talking about commercial grade mirrors ass hat, not hughly expensive labratory grade mirrors.

In any case whether the mirror is 99% or 90% is moot once it has been exposed to the elements for a couple of days.

So we have yet another idiot that can't understand that from ground level the Sun is "up", i.e. has a positive elevation angle.