Excellent point Dean.
The drawbacks to "Clean Energy" production are seldomly reported. I live near one of the largest wind farms in the country and I personally love seeing them. Locally, the raptors losses are reported, I'm not sure how accurate the surveys are or if others across the contry see them.
And as to further the point, I've done work at a very large Geothermal plant. I'm sure many people have no idea the dangerous minerals and substances the accompany the steam that is use the run the turbines or how these dangers need to be dealt with and the expense.
So I'd like to concur with you and say that orbital base solar collection couldn't be any worse.

Dean,

You're just such a poopy head.

I feel in my vapid little bones that solar is the way to go. Rumsfield is hiding the truth from us. In fact, solar flux is many times what the oil lobby says it it. They're lying. They're all lying...

My hamster told me, and she wouldn't fib.

Pardon me while I wipe the foam from my lips...

Large solar panel power generation might make sense when you build huge arrays in gravity stable location like L4 & L5 in the Earth-Moon system. You then beamed the energy back to Earth via geosynchronous relay stations and ground station. The ground station will of course be complete devoid of life.

That was at least the thinking in the '70s.

That's a bit low, Dean. The solar flux intersecting Earth's cross-section is 1.37 kilowatts per square meter. That's the intensity at noon on the Equator.

Then you spread that onto the area of the globe, including the night side, and you get a day-and-night, all-latitude, all-season average of 342.5 watts per square meter.

http://scienceworld.wolfram.com/astronomy/SolarConstant.html

http://www.ngdc.noaa.gov/stp/SOLAR/IRRADIANCE/irrad.html

There may be storage options other than batteries. One way would be to use the electricity to make hydrogen from water, then store the hydrogen in tanks, then use it as necessary--either by burning it in turbines in the classical style, or using fuel cells if they ever work.

Totally agree that many environmentalists ignore the practical details.

When I said if (fuel cells) ever work, I meant, of course, work *economically*.

Let's look at this from an economic perspective. Say 345 W/m^2 is the power we can extract. Who the heck would want a square meter of solar panel just to run 1 PC? 345 W is not a whole lot of power.

We're talking TW needed on a global scale. This means 10,000,000,000 m^2 of collecting surface. Say the collecting surface is 10 cm deep (including the support trusses, etc.) A crude calculation with the density of silicon, 2,330 kg/m^3, shows this is a mass of 2,330,000,000,000 kg, or about 2.6 billion tons. The cost of lifting that much mass into orbit is prohibitive.

Also consider the problem of beaming several TW of power through the atmosphere without ionizing it to smithereens.

Finally, think of how much collecting surface we would need on the downlink to capture TWs of power, without melting the collecting surface.

As has been pointed out, your figures are off by about an order of magnitude. Even given the day night cycle, cloud cover, and the ineffeciences of cheap solar cells (let alone the good ones) the area of an average family's house is sufficient to provide for that family's power needs via solar arrays. The trick is, of course, storing the power so that it can be used throughout the day and night. Unless we have some magic dohicky to do that then it's probably not going to be a feasible power source any time soon.

Also, Samuel, your numbers concerning the density of Solar Arrays in orbit are in error by more than several orders of magnitude.

P.S. Your comment filter is faulty, annoying, and has a father that smelt of elderberries.

Guys: The references RJSmith gave (here and here give the solar constant as 1.37 kilowatts outside the Earth's atmosphere, not on the surface.

I'll do a little digging, since I was working from memory, but I'm pretty sure it's closer to 100 watts per square meter by the time you filter all the way through the atmosphere. Which is why orbital collectors are a much better deal than trying to put all those panels on the surface.

Okay, I just checked Wikiepedia, and it says the same thing right here: "The solar constant is the amount of incoming solar radiation per unit area, measured on the outer surface of Earth's atmosphere. It is calculated to be roughly 1367 watts per square metre."

Which is why orbiting collectors are a good idea.

The last engineer I actually asked about this said that at the earth's surface near the equator at high noon, the constant was closer to 100 watts. If I'm mistaken I would of course be happy to correct, but in doing a little digging I'm not finding it.

Dean, the solar flux at the surface of the earth when the sun is at the zenith is roughly 1 kW/m^2. 100 W/m^2 sounds like something approximating the maximum you can get out of a collector with near-term practical technology averaged over a day. (Integrate over a day and the average is 1/pi of the peak, 30% conversion efficiency is pretty close to the maximum you can get with current technology photoelectric, although cost effective photoelectric is more like 10%).

Well, I'll buy that. In any case, the challenge remains the same: you lose enormous amounts of energy filtering through the atmosphere, having to deal with cloud cover, night time, and so on. Practically speaking the loss is huge. Add in to this the fact that to make practical use you either have very specialized applications or lots and lots of batteries, and the problem becomes apparent.

Although it's surely the case that solar does get a little more practical all the time, as collectors grow more efficient and devices that have lower power consumption requirements become increasingly available. But it'll never be a long-term answer barring some kind of miracle like room-temperature superconductors or somesuch.

You don’t need fuel cells or batteries to store energy, compressed air will do it, so will water and hydraulics (which is a little different then using water).

Clearly there aren’t many engineers here. Or maybe just not any creative ones. And since the energy is free the energy loss in the transfer is sort of irrelevant.

I also think your information about wind and soler is a bit off, there are people right now living totally off the grid with renewables and runnig a comeplete array of home appliances. Sure there are some very important gotchas, but its being done right now and neary a fule cell in sight.

If you all put as much though into renewables as you do into fuel cells which are a total boondoggle you might just see that these things aren't as bad of a deal as you making them out to be. But I do have to chuckle at one thing, your all so concerned at the environmental impact of renewable yet you all like to overlook the rather substantial impact of coal and things like the breeder reactor (and I’m not against those things either as they will form a very important part of our future energy strategy but renewables are practically benign compared to Coal and Nukes ).

But the fact is that serious research into renewables are in it’s infancy and you all seem so willing to write it off, as opposed to fuel cells which have been with us since the 60’s and is, by comparison a mature technology which you should consider a technology for stationary power and will not be able to be a suitable transportation technology, at least for pivate autos.

It does not seem likely that renewables will ever become a wholesale replacement for other energy technologies but they will become and important adjunct.

Hey, Rick, if renewables are such a great idea, why is research "still in its infancy," after 30 years of energy crisis, hm?

Now, I can see some of the disadvantages to coal, including miner's health problems, and high-sulfer coal (although the latter can be addressed with scrubbers). What's so non-benign about nuclear power? Don't tell me you're going to bring up Chernobyl again? AKA "the plant that was neither designed nor built in the US?" Recall that the United States is country where more people died in Ted Kennedy's car than in all commercial nuclear accidents, combined.

If solar energy or any other "alternative" source of energy ever does become practicable, the eco-radicals will find some reason to oppose it. A few months ago, I read that they opposed building windmills on some hills in New Jersey supposedly because the windmills would spoil the scenery. The eco-radicals are enemies of Western civilization and that's all they are.

You may find Geoffrey Landis's paper interesting:
http://gltrs.grc.nasa.gov/cgi-bin/GLTRS/browse.pl?2004/TM-2004-212743.html

I think the problem with environmentalists is that they never stop to think what works best. So anything will have furious opponents and nothing will have serious support. Therefore, everything must be banned.
That's why I had to end my short career as an environmentalist.

Rick is always good at snarking and dismissing anyone who disagrees with him and unfortunately almost never provides anything in the way of clickable links or other references you can actually look at.

Here's a clue Rick: "You're all stupid and if you'd just do your homework you'd see I'm right" doesn't go very far. The last time you did it you did provide SOME references, but jeez man. You have your own weblog. Why don't you start writing these pieces that prove your points and just start linking us to those? Good gracious.

I am particularly amused at this blanket assertion that "renewables" (which ones?) are without hazards, when of course all of them involve environmental and other hazards when it comes to electrical generation. Physicist Bernard Cohen in his book Before It's Too late demonstrated using verifiable peer-reviewed sources that so far as electrical generation is concerned, solar power is indeed more environmentally hazardous than standard nuclear power including the risk of nuclear waste, precisely because of the waste issues involved in the construction of solar cells, the use of batteries, and the risks entailed in the installation and repair and disposal of solar cells once they burn out.

Mind you, as I already said, using solar for heating and cooling is a different matter. Nevertheless all the so-called "renewables" (depending on which ones you're talking about) involve dangers and environmental impacts. Some greater than others, of course.

Yes, there are people living lives completely off the grid. Usually living quite restricted lives and spending lots of extra money to do it from what I've seen, and often being net contributors to environmental damage (I don't know about all of them but some of them certainly are), but yeah they're out there.

I again note that I do not count systems which make efficient use of sunlight for heating and cooling purposes. I speak of electrical generation.

People like Rick have obviously never spent a winter in Chicago. How much heat/electicity/whatever does a solar array deliver in the 2nd week of solid overcast sky with temperatures in the teens? Not to mention that the sun isn't overhead but is only about 45 degrees high?

Dean,

I write extensively on this subject on my site. Complete with links and all the attendant stuff. You should spend more time over there. Typically when you do you never really take much exception to the things I write so I can only assume you agree [grin].

I never said anyone was stupid, just mis-informed and if you want specifics then ask. I need to know exactly what you think I said was not fact. That would streamline the process. We also have to define terms. But you know what, precious few other people never provide links when they take me to task, but it seems as if it is incumbent on me to provide them, why, because I disagree? I guess if I join the chorus of sycophants I get a pass on backing up what I say. Case in point:

Casey said that there are few disadvantages to coal, no back up link, just an assertion. In fact his entire rebuttal is assertion, but no one here seems to be uncomfortable with it despite the fact that there are problems with coal beyond the things he mentioned, but he gets a pass. But the fact is I’m in favor of coal, I in favor of anything if approached intelligently, but there in lies the problem most of the time.

Also you people like to shift ground, I stated very clearly that renewables will never become a wholesale replacement for other energy technologies but they will become and important adjunct. Then you go off talking about solar completely replacing other technologies. This is called a straw man argument. Also your peer reviewed research seems to be making some assumption (I haven’t read it yet, but I will), One of which is an egregious mistake, that batteries are the only ways to store electricity, there are not and the methods are pretty numerous.

Fred, born and raised in Michigan and I know a little about cold weather. But your question is irrelevant because I have never said that solar is a complete replacement technology, nothing is, again ... straw man.

I thought the article was suppose to be on global dimming, not on solar power. In the whole article there are only 2 sentences about global dimming. This article was no impact on my global dimming report for school. Thank's alot Dean!