Do large arrays of solar cells reduce global warming?

Question

Assuming that solar cells can be made inexpensively and are efficient (I know this isn't the case), wouldn't the cells absorb the energy that would otherwise be reflected back into the atmosphere? Also when I mean large, I don't mean square feet, but several square miles of solar cells.

Answer 1

Solar photovoltaic cells are much more expensive than wind turbines as a means to produce electricity.

The cost of electricity produced by wind turbines is approximately 4 cents per kilowatt hour(1)

That is less than the cost of production of electricity by the use of Natural Gas and only slightly more than the cost of production of electricity when Coal is used as the fuel.

The best way to stop Global Warming is to stop the use of fossil fuels for electricity production.

The best way to encourage people to use electricity that is generated without the production of Carbon Dioxide is to make certain that the cost of production of the electricity is not significantly higher than the cost of production of electricity produced by fossil fuels.

The only source of electricity that does not produce Carbon Dioxide or other toxic waste and has a cost of production close to the cost of electricity produced by fossil fuels is electricity produced by wind power.

The cost of production of electricity by the use of solar photovoltaic cells is approximately 10 times higher.

Answer 2

Good point.
Some of the energy (85%) is absorbed and is converted to heat.
The remaining 15% is converted to electricity.

You want to ask how much would be reflected back normally. Not 100%, surely.
But Ok, solar cells, being dark absorb more energy than, say, a white desert.

However, three other things come into play.
1. We are adding warmth (energy) to our atmosphere now that would not be there if we ran everything on solar cells.
2. If things get slightly warmer during the day, they also radiate more heat. Warmer things (solar cells, deserts, planets) radiate more heat. A balance will be found.
3. If everything runs on solar power, the amount of greenhouse gasses will decrease, and we'll have less of a 'blanket' around the earth. We will loose heat more easily.

Consider the difference between a white car in the sun, with the heater on and a blanket on top, or a dark car with the heater off and no blanket.

Answer 3

I see what you're saying. The problem is a little more specific than energy being reflected back into the atmopshere. If it's simply a matter of reflection than it's not a problem.

The sunlight reaching us does so in the form of short wavelength solar radiation, when this is absorbed by surfaces such as buildings, oceans, the earth itself, it is subsequently re-radiated back out when the ambient temperature drops. The re-radiated energy is in the form of longer wavelength thermal radiation and it's the fact that it has a longer wavelength that causes it to be retained within the atmosphere by the greenhouse gases.

If we were to simply place mirrors on the ground they would reflect back almost all the solar radiation striking them. This would be a lot simpler than using photovoltaic cells, although of course no energy would be produced.

Even the mirror idea isn't quite so simple. To be most effective they need to track the sun so that the sunlight strikes at a perpendicular angle, this means complex mechanisms are needed to move the mirrors - something akin to the giant radio telescopes. Not only is this hugely expensive but it uses a lot of energy and is only effective during daylight hours when the sun is shining.

However, place the mirror is space and it doesn't matter what the weather is doing and the movement of the mirror can be computer controlled by very small 'solar sails', themselves being powered by the sun. Further, in space the mirrors need only be microscopically thin and could weigh as little as one gram each (jncluding computer and sails).

It might all sound far fetched but it's already been examined and similar research has been conducted by a team led by British Astronomer professor Roger Angel.

Answer 4

Solar electric is inexpensive. It pays you back. How much will you pay renting electric from the local utility over the next 30 years? Remember to add in the cost of fuel increase and the cost of living increses. You will spend on avg over 100 grand.

Has your car paid you back for it's cost yet? I did not think so. How about that pack of smokes you have on your desk? How much is that paying you back over your life time. What about that Big Mac that you eat every day for lunch. Is it paying you back? I think not being you gain weight and have doctor bills and die young.

Now speaking of dieing early because of our bad habits. We are putting trash in our air and killing ourselfs out as well. If we were using solar we would be limiting how much garb we breath.

The idea is to reflect the light back into space to help keep our planet cooler. But being we are putting so much garb in the air it collects the heat from the light and makes it hotter.

So YES by having miles of solar panels to produce electric we would not use as much coal and guess what.... Yup less garb in the atmosphere to collect heat. And we will not need to put toxic wast from nuke power plants in land fills that will kill us out.

Solar power is good no matter how you want to shake up the jar.

Answer 5

You're right that this effect would reduce the positive effect cells would have on global warming. But....

I still think they'd still reduce global warming, just not quite as much. You wouldn't be putting them where it ever snows (not large power plants of them), so they're replacing relatively dark land. Not that much worse.

Answer 6

someone once tried this a lengthy lengthy time period in the past, because they did not compared to what the electromagnetic radiation from the gentle become doing to the planet. Their plan to plunge the international into darkness turned right into somewhat more straightforward, although, yet become nonetheless an attempt to flee their punishment by technique of God. They wanted to rob the planet of sunshine and take care of our planet's skill fields, yet they failed and were cursed for this.

Answer 7

That is part of the real problem , to assume that global warming is real.