For a minute there I thought I had to get off my couch, when all the while the fact is we don't have to do anything much but keep things afloat for just a few decades more! In fact, we'd best shut up about PO, because if our offspring finds out we knew about it all along, they'll turn and wring our necks come 2036!
Joined: Aug 03, 2006 Posts: 4069 Location: Graceland
Posted: Tue Feb 26, 2008 8:36 pm Post subject: Is Solar Power a Perpetual Motion Machine?
Either it is or it isn't. I suspect it isn't. If it isn't, then won't the inputs necessary for large scale solar projects be subject to the same peak as peak oil at some point in the future? In other words, it's not really "sustainable" at all.
Assuming for a moment that solar is scalable in the first place, isn't it subject to the same "least abundant necessity" problem that limits any system?
If solar is ultimately just another resource intensive energy source (though far less efficient and versatile than fossil fuels), then isn't solar really an enormous step backwards from where we are now (assuming that it doesn't have a negative EROI when you really take a hard look at it)?
The reason I am picking on solar is that I think many people view solar as a "renewable" resource, as opposed to a non-renewable resource like fossil fuels. But if the solar panels, batteries and other equipment involve large inputs of silver, lead, iron, glass, copper, etc., how is that renewable? I guess some of it can be recycled, but not all of it.
I don't want to start a "peak everything" discussion. I just think that people have the wrong idea about solar. _________________
Joined: Sep 25, 2004 Posts: 4416 Location: Boston, MA
Posted: Tue Feb 26, 2008 9:34 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
BigTex wrote:
Either it is or it isn't. I suspect it isn't. If it isn't, then won't the inputs necessary for large scale solar projects be subject to the same peak as peak oil at some point in the future? In other words, it's not really "sustainable" at all.
Assuming for a moment that solar is scalable in the first place, isn't it subject to the same "least abundant necessity" problem that limits any system?
If solar is ultimately just another resource intensive energy source (though far less efficient and versatile than fossil fuels), then isn't solar really an enormous step backwards from where we are now (assuming that it doesn't have a negative EROI when you really take a hard look at it)?
The reason I am picking on solar is that I think many people view solar as a "renewable" resource, as opposed to a non-renewable resource like fossil fuels. But if the solar panels, batteries and other equipment involve large inputs of silver, lead, iron, glass, copper, etc., how is that renewable? I guess some of it can be recycled, but not all of it.
I don't want to start a "peak everything" discussion. I just think that people have the wrong idea about solar.
It depends heavily on what you mean by solar power or how you make the solar panels
If we build solar thermal towers instead of a fleet of solar panels, the inputs are far less rare-material intensive.
Basically you need glass to make the mirrors, steel to build the structure and some copper wires to connect it all.
If we're talking about solar PV panels, the main input is silicon (sand). But there are many other kinds of PV panels available that are made out of other kinds of materials. Nanosolar, for example, uses aluminum film. _________________ "www.peakoil.com is the Myspace of the Apocalypse."
Joined: Mar 19, 2007 Posts: 162 Location: Ontario, Canada
Posted: Tue Feb 26, 2008 9:58 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
It is and it isn't.
Eventually, the sun will burn out. At that point, all the solar collection tech in the world won't help.
But it is a perpetually renewing source as long as it lasts. If you trace things back far enough, one of only 2 sources.
We have fissionables, and we have solar energy. Everything else we use for power or energy is derived from one of these 2 sources.
If used wisely, and with appropriate lifestyle changes, population controls, etc., it is reasonable to believe the planets energy needs can be met by harvesting the energy that falls on it from the sun. _________________ If we knew what we were doing, it wouldn't be called research. ~A. Einstein
TANSTAAFL ~R.A.H.
The best time to plant a tree is 20 years ago. The next best time is today. ~Chinese proverb
Joined: Aug 03, 2006 Posts: 4069 Location: Graceland
Posted: Tue Feb 26, 2008 10:05 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
DavidFolks wrote:
It is and it isn't.
Eventually, the sun will burn out. At that point, all the solar collection tech in the world won't help.
But it is a perpetually renewing source as long as it lasts. If you trace things back far enough, one of only 2 sources.
We have fissionables, and we have solar energy. Everything else we use for power or energy is derived from one of these 2 sources.
If used wisely, and with appropriate lifestyle changes, population controls, etc., it is reasonable to believe the planets energy needs can be met by harvesting the energy that falls on it from the sun.
For our purposes, though, I am concerned with whether the solar collection devices are what makes it non-renewable. I understand that oil is a very concentrated product of solar processes, but it is SO MUCH MORE concentrated than the solar energy we gather with panels that it really makes the solar panels look kind of rinky-dink. _________________
Posted: Tue Feb 26, 2008 10:50 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
DavidFolks wrote:
If used wisely, and with appropriate lifestyle changes, population controls, etc., it is reasonable to believe the planets energy needs can be met by harvesting the energy that falls on it from the sun.
The planet's energy needs have always been met by the sun.
Man's modern techno-world and his overshoot population energy needs can never be met by solar.
Why? Because solar energy could never have caused us to overshoot the carrying capacity, therefore, it cannot support the overshoot population bloom.
Only if we powerdown and reduce the existing population to a sustainable level of somewhere around 2 to 3 billion will solar ever meet our needs on a sustainable basis.
We will try, and for a short time, perhaps succeed in some fashion, but only with further environmental degradation and loss of carrying capacity in the process. _________________ A Saudi saying, "My father rode a camel. I drive a car. My son flies a jet-plane. His son will ride a camel."
Live in Arizona? Check out: http://sustainablearizona.org and read my blog.
Joined: Aug 03, 2006 Posts: 4069 Location: Graceland
Posted: Tue Feb 26, 2008 11:11 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
MonteQuest wrote:
DavidFolks wrote:
If used wisely, and with appropriate lifestyle changes, population controls, etc., it is reasonable to believe the planets energy needs can be met by harvesting the energy that falls on it from the sun.
The planet's energy needs have always been met by the sun.
Man's modern techno-world and his overshoot population energy needs can never be met by solar.
Why? Because solar energy could never have caused us to overshoot the carrying capacity, therefore, it cannot support the overshoot population bloom.
Monte, we may be saying the same things in a different way, but I would say that it is the millions of years of solar energy stored in the elegant form of fossil fuels which HAS PERMITTED us to get into overshoot in the first place.
Absent this lucky one time discovery of concentrated solar power we would never have crept beyond sustainability (or not much anyway).
Posted: Wed Feb 27, 2008 12:41 am Post subject: Re: Is Solar Power a Perpetual Motion Machine?
BigTex wrote:
Absent this lucky one time discovery of concentrated solar power we would never have crept beyond sustainability (or not much anyway).
So it's the sun's fault.
Well, yes. But we didn't have to squander it all in less than 150 years.
And one-time is the key word here. There will never be a better energy source than oil, nor it's equivalent.
No matter how hard we try or hope.
We've shot the big wad. _________________ A Saudi saying, "My father rode a camel. I drive a car. My son flies a jet-plane. His son will ride a camel."
Live in Arizona? Check out: http://sustainablearizona.org and read my blog.
Joined: Aug 03, 2006 Posts: 4069 Location: Graceland
Posted: Wed Feb 27, 2008 1:03 am Post subject: Re: Is Solar Power a Perpetual Motion Machine?
MonteQuest wrote:
BigTex wrote:
Absent this lucky one time discovery of concentrated solar power we would never have crept beyond sustainability (or not much anyway).
So it's the sun's fault.
Well, yes. But we didn't have to squander it all in less than 150 years.
And one-time is the key word here. There will never be a better energy source than oil, nor it's equivalent.
No matter how hard we try or hope.
We've shot the big wad.
See my recent post about the Human Mind and Long Term Strategy. I agree that it was folly to use up the gift of oil in 150 years, but I'm not sure we could have done it differently. I'm not sure humans are capable of grasping problems that unfold over the span of more one lifetime. From an evolutionary perspective, up until recently there would have been zero survival value in having the ability to comprehend threats unfolding over that kind of time period. Thus, we handle one, five and ten year problems WAY better than we handle 50, 100 and 200 year problems.
Cognitive dissonance is not a strong enough term to capture the inability of most people to grasp what you're talking about. I think it is literally a blind spot in human reason (or maybe the same part of us that allows us to live with the knowledge of our eventual death without being bothered by it too much). Getting past it doesn't mean you have any special insight, it just means that you put your preconceived notions down long enough to see something that is very obvious, it's just that the human imagination doesn't want to acknowledge it.
People here fight it and fight it and fight it. They think they are being open minded, and maybe they are, but some minds just can't seem to open up wide enough to grasp the problem you are describing. OTOH, once you do begin to grasp it you see that it's not doom, it's just reality. Doom is an interpretation.
Malthus was right, he just didn't factor oil powered overshoot into his theory. _________________
Posted: Wed Feb 27, 2008 1:34 am Post subject: Re: Is Solar Power a Perpetual Motion Machine?
BigTex wrote:
Either it is or it isn't. I suspect it isn't. If it isn't, then won't the inputs necessary for large scale solar projects be subject to the same peak as peak oil at some point in the future? In other words, it's not really "sustainable" at all.
Nothing is really sustainable over a long enough time period. So, it depends on how long you're talking about. _________________
Posted: Wed Feb 27, 2008 3:17 am Post subject: Re: Is Solar Power a Perpetual Motion Machine?
Oil and other fossil fuels are nothing but converted ancient sunshine.b Life itself is based on the energy coming from the sun. So is wind power, even hydro-electric is just energy from the sun in a different form.
In the future our sun will burn out. The sun is not renewable, that's for sure. It's unlikely that we humans will be around to watch this spectacular show. _________________ I am a sarcastic cynic. Some say I'm an asshole. Now that we have that out of the way ...
Last edited by Lighthouse on Wed Feb 27, 2008 3:33 am; edited 3 times in total
Joined: May 06, 2006 Posts: 830 Location: Tustin, CA
Posted: Wed Feb 27, 2008 3:19 am Post subject: Re: Is Solar Power a Perpetual Motion Machine?
BigTex wrote:
Either it is or it isn't. I suspect it isn't.
Your right. It’s only for about another billion years (with a “B”). I’m one of the amateur astronomers on the site; Shannymara is another if you don’t believe me.
But for those of you who only want to know a way to cook your food and purify the water you drink read this site! :
Solar Link _________________ Skeptical scrutiny in both Science and Religion is the means by which deep thoughts are winnowed from deep nonsense-Carl Sagan
Posted: Wed Feb 27, 2008 4:58 am Post subject: Re: Is Solar Power a Perpetual Motion Machine?
Well, the first point to make is in regard to the title of the thread.
We are not dealing with a perpetuum mobile here for sure, because that refers to the idea of a machine (using the word in the most general possible sense) that outputs more energy than is input. A solar panel or other machine with solar energy as input, nobody is suggesting that E(in)<E(out).
The second point which hasn't been mentioned yet is that by a trivial calculation you can show that even including albedo effects, the rate of energy coming onto the Earth's surface from the Sun is ~10^17W. The human population's consumption is of the order of 10^13W. This is a ratio of 10000:1.
To get an accurate figure of solar realistically available is obviously a tall order, but four orders of magnitude ought to tell you something.
Linky 1 Linky 2
Posted: Wed Feb 27, 2008 5:17 am Post subject: Re: Is Solar Power a Perpetual Motion Machine?
MonteQuest wrote:
The planet's energy needs have always been met by the sun.
This statement actually has no semantic content, largely because of the word "needs".
The Universe's need for hydrogen has always been provided for.
Quote:
Man's modern techno-world and his overshoot population energy needs can never be met by solar.
Why? Because solar energy could never have caused us to overshoot the carrying capacity, therefore, it cannot support the overshoot population bloom.
Think carefully about this. The first sentence asserts overshoot.
The second sentence points out that solar could never have been the cause of overshoot (presumably in some past scenario where solar was taken up before fossil fuels), and I presume you base that on the fact that solar is not a source that will deplete (on sub-billion year timescales). Very reasonable.
Then you deduce that solar will not prevent the overshoot for this reason. The deduction is based on the assumption of overshoot! If the assumption is not valid, then "population energy needs can never be met by solar" does not follow.
If carrying capacity with solar is higher than carrying capacity with fossil fuels, then this reasoning doesn't work. (And yes, theoretically, the carrying capacity doesn't actually change, but in this scenario we are nowhere near our carrying capacity yet).
Quote:
Only if we powerdown and reduce the existing population to a sustainable level of somewhere around 2 to 3 billion will solar ever meet our needs on a sustainable basis.
Another assertion with no support. It's not that I think it's an outrageous, or even wrong, but give at least some reason for thinking it.
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