How then, do we move backwards? How does a society, with most of the people having no clue of future events, move from being dependent on a vast and intertwined network of goods and services produced by the indigenous people of whereever, to a local resource and renewable energy based society, and do so in the timeframe available (20-30 years using the most liberal extimates, 10-20 with resonable estimates, 5-10 with worst case scenarios), all the while prices on everything increasing, world politics getting more militaristic, governments continuously reducing civil liberties, shortages of goods on the market and weather patterns resembling bad Hollywood movies?
Posted: Wed Feb 27, 2008 5:18 am Post subject: Re: Is Solar Power a Perpetual Motion Machine?
SILENTTODD wrote:
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.
I thought we were about halfway through main sequence burning? So we'd have about another 4-5 billion years to go before moving into the red giant phase? My memory may be a little "corrupted" on this but that's what I remember being taught.
Joined: Mar 19, 2007 Posts: 162 Location: Ontario, Canada
Posted: Wed Feb 27, 2008 7:13 am Post subject: Re: Is Solar Power a Perpetual Motion Machine?
BigTex wrote:
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.
I maintain that there is enough energy to support our technologically advanced race, at our current population, without further environmental degradation, through the use of solar and solar derived energy only. There are some things we'll have to do better, and smarter.
For instance, it is more efficient to passively heat by solar, than to capture, convert to electricity, jam into a battery, pull out of a battery and convert to heat. For that matter, it makes more sense to build in such a way as to require very little in the way of supplemental heating and cooling.
We don't have to rely solely on solar panels to reap the benefits of solar energy. Wind is solar derived, build windmills where appropriate. Hydro-electric is solar derived. I'm not suggesting we indiscriminately flood huge sections of land, but microelectric generators can be used where appropriate. Tidal power is a huge force to be tapped.
MonteQuest wrote:
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.
Well hi MonteQuest. Long time no see. I haven't had the pleasure of fencing with you semantically for awhile, so I'll take a stab at it now.
First, I'll grant you the first hit. The planet's needs have always been met by the sun. Verbal shorthand, my bad.
What I meant to say is:
DavidFolks wrote:
I maintain that there is enough energy to support our technologically advanced race, at our current population, without further environmental degradation, through the use of solar and solar derived energy only.
Please note that I did not now, nor have I ever said that we could support the profligate waste, and overconsumption of the north american life style.
I will not grant you that we are in overshoot. I will grant you that significant portions of the race are consuming above their needs at the expense of others, and of the environment. I maintain that a more equitable distribution of resources, and a more reasoned approach to supplying needs would balance the equation.
MonteQuest wrote:
There will never be a better energy source than oil, nor it's equivalent.
Oil is not a source of energy. Oil is a battery. Oil is a very densly packed battery, but a battery none the less. As batteries go, it is grossly inefficient. It takes an inordinate amount of energy input, over thousands of years to charge, and the discharge rate is almost instantaneous. Plus, it has only one charge cycle.
With significant changes to lifestyle, consumption, building and transportation practices, commerce, manufacturing, all aspects of life as we know it, we can learn to live within the planet's carrying capacity. _________________ 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: May 06, 2006 Posts: 811 Location: Tustin, CA
Posted: Wed Feb 27, 2008 4:23 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
ekaggata wrote:
SILENTTODD wrote:
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.
I thought we were about halfway through main sequence burning? So we'd have about another 4-5 billion years to go before moving into the red giant phase? My memory may be a little "corrupted" on this but that's what I remember being taught.
You're right on that. The billion years I was referring to is the period the sun has left to be more or less stable as we see it today. Everything I’ve read points to that time duration before the core of the sun becomes so depleted in hydrogen, the fusion process starts moving to outer layers around the core and the sun will start becoming larger in size. Whether it becomes so large it will envelope the earth has been debated, but life on this planet will end long before that because of it. _________________ Skeptical scrutiny in both Science and Religion is the means by which deep thoughts are winnowed from deep nonsense-Carl Sagan
Joined: Aug 03, 2006 Posts: 4043 Location: Memphis
Posted: Wed Feb 27, 2008 5:53 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
The thesis of the OP was not that the sun was a perpetual motion machine--the perpetual motion machine is the manmade device that collects and stores the sun's power that is supposed to provide any net energy gain over the input costs of such a device.
We are talking about replacing millions of years of accumulated sunlight in the form of oil with this afternoon's accumulation of sunlight in the form of solar electricity and hot water.
Solar power as an alternative to oil reminds me of a prosthetic limb as an alternative to an arm. It's better than nothing, I suppose, but to call it a "replacement" is a stretch. _________________
Posted: Wed Feb 27, 2008 6:20 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
To the question in the subject line, No it isn't a PMM.
Since most solar panels today are made from glass, silicon (sand) and steel I don't see the lack of resources as an issue any more than it is for making houses.
The amount of available energy from the sun can easily replace the amount of energy oil provides us. Yes, more expensively, but the energy is there. And solar will last a lot longer than oil will;)
With improvements in technology I suggest that solar energy will become more efficient which will make it easier to replace other forms of energy.
Don't get me wrong, I believe the best solution is a combination of solar, wind, hydro and nuclear.
Joined: Sep 25, 2004 Posts: 4359 Location: Boston, MA
Posted: Wed Feb 27, 2008 6:25 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
Sunlight that hits the Earth's surface does two things. It warms the ground and allows plants to grow.
If you cover over plants in order to absorb sunlight, the biosphere suffers.
If you cover over desert...it's free energy. Nobody is using it. It's not perpetual motion if the energy isn't being used for anything. Every night, the energy radiates off of desert sand and back into space.
What about if we cover over our rooftops with solar panels?
That's another way to get solar energy that isn't be used for anything.
Very little of the energy absorbed by plants over millions of years turned into oil. That takes care of the "but the oil formed over millions of years" argument. _________________ "www.peakoil.com is the Myspace of the Apocalypse."
Joined: Aug 03, 2006 Posts: 4043 Location: Memphis
Posted: Wed Feb 27, 2008 6:45 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
Zythryn wrote:
To the question in the subject line, No it isn't a PMM.
Since most solar panels today are made from glass, silicon (sand) and steel I don't see the lack of resources as an issue any more than it is for making houses.
If lack of resources for the solar equipment is not an issue right now, why do you suppose that is? Perhaps because there is a fossil fuels powered mineral extraction infrastructure? What happens when that is gone or suddenly VERY expensive to operate?
Houses are not supposed to provide a net energy gain, so it's not a good comparison.
Quote:
The amount of available energy from the sun can easily replace the amount of energy oil provides us. Yes, more expensively, but the energy is there. And solar will last a lot longer than oil will;)
Yes, but you have to save it up for millions of years in the form of fossil fuels to have enough of it to run our global infrastructure.
Yes, it is more expensive, a LOT more expensive, and not scalable.
No, the energy is not there, not right now. Oil is millions of years of stored solar energy. You can't hope to harvest this afternoon's solar energy to replace it.
I agree that the sun will last longer than oil will at the rate we are burning it, but I don't think that helps answer the question of how we will be able to utilize the sun's energy in a manner that will provide a meaningful solution to the depletion of fossil fuels.
Quote:
With improvements in technology I suggest that solar energy will become more efficient which will make it easier to replace other forms of energy.
Don't get me wrong, I believe the best solution is a combination of solar, wind, hydro and nuclear.
Solar energy won't become more efficient (the sun's the sun), but our ability to store it probably will. The most efficient storage device in the world, however, will not approach the energy density of fossil fuels. It's comparing a prosthetic to a human arm.
BTW, how do you make corn grow without petroleum based fertilizer?
You sound like a Chevron commercial. (Just kidding.) _________________
Joined: Aug 03, 2006 Posts: 4043 Location: Memphis
Posted: Wed Feb 27, 2008 6:50 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
Tyler_JC wrote:
Very little of the energy absorbed by plants over millions of years turned into oil. That takes care of the "but the oil formed over millions of years" argument.
I think it raises an interesting issue, but I don't think it ends the argument. Even if only 1% of the energy absorbed by plants turned into oil, if we are talking about a long enough time frame that could easily exceed the amount of solar energy that is available this afternoon to convert to electricity or hot water. _________________
Joined: Sep 25, 2004 Posts: 4359 Location: Boston, MA
Posted: Wed Feb 27, 2008 7:03 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
BigTex wrote:
Tyler_JC wrote:
Very little of the energy absorbed by plants over millions of years turned into oil. That takes care of the "but the oil formed over millions of years" argument.
I think it raises an interesting issue, but I don't think it ends the argument. Even if only 1% of the energy absorbed by plants turned into oil, if we are talking about a long enough time frame that could easily exceed the amount of solar energy that is available this afternoon to convert to electricity or hot water.
It does end the argument, in my opinion.
The fossil fuel endowment of the Earth is a rounding error compared to the availability of solar power.
Shamelessly stolen from wikipedia:
* The total solar energy available to the earth is approximately 3850 zettajoules (ZJ) per year.
* Oceans absorb approximately 2850 ZJ of solar energy per year.
* Winds can theoretically supply 6 ZJ of energy per year.
* Biomass captures approximately 1.8 ZJ of solar energy per year.
* Worldwide energy consumption was 0.471 ZJ in 2004.
It's not even close.
There is far more solar power available than we could ever possibly consume given a human population on the verge of peaking.
It just takes effort to capture the stuff and so far, we haven't even begun to try.
As for growing corn without petroleum based fertilizers, we only use natural gas to make fertilizer because it's the cheapest. We don't actually use oil to make fertilizer, we use it as fuel source to move our tractors around. _________________ "www.peakoil.com is the Myspace of the Apocalypse."
Joined: Aug 03, 2006 Posts: 4043 Location: Memphis
Posted: Wed Feb 27, 2008 10:09 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
Tyler_JC wrote:
The fossil fuel endowment of the Earth is a rounding error compared to the availability of solar power.
Shamelessly stolen from wikipedia:
* The total solar energy available to the earth is approximately 3850 zettajoules (ZJ) per year.
* Oceans absorb approximately 2850 ZJ of solar energy per year.
* Winds can theoretically supply 6 ZJ of energy per year.
* Biomass captures approximately 1.8 ZJ of solar energy per year.
* Worldwide energy consumption was 0.471 ZJ in 2004.
It's not even close.
There is far more solar power available than we could ever possibly consume given a human population on the verge of peaking.
It just takes effort to capture the stuff and so far, we haven't even begun to try.
As for growing corn without petroleum based fertilizers, we only use natural gas to make fertilizer because it's the cheapest. We don't actually use oil to make fertilizer, we use it as fuel source to move our tractors around.
Should have said fossil fuel on the growing corn comment, but I think the point is the same--no fossil fuel, no corn. Tractors, ships, trucks, trains, irrigation pumps--will they all run on batteries?
I think the bottleneck on solar is not the amount of solar that could potentially be stored as energy for later consumption, but rather the collection devices. Do you think that it is practicable to build out the infrastructure you would need to gather and store the amount of solar energy it would take to replace any significant portion of the energy we consume right now?
Is technology the answer? So far, technology has only led to higher levels of energy use; why will future technology require lower energy inputs than it has so far? All I see with technology is an upward spiral of technology with diminishing returns on each extra unit of complexity.
What is the EROI on solar power collection?
Do you think that the total solar power that reaches the earth is a little like talking about the gold that is diluted in seawater? It's interesting, but given that so little of it can be harvested is it maybe a little misleading?
Do you believe that the basket of alternatives can replace fossil fuels? Do you think it can support the current population? if yes, do you think the current population can expand? If you think carrying capacity is below the current level, where would you peg it?
I'm still not clear on how the basket of alternatives provides enough food for the current population. _________________
Joined: Aug 03, 2006 Posts: 4043 Location: Memphis
Posted: Wed Feb 27, 2008 10:13 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
Narz wrote:
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.
You can't say that for sure. Who would of thought we'd discover oil?
But the population exploded after we discovered oil. You can't depend upon an undiscovered miraculous oil replacement when you already have 6 billion to feed.
Joined: Sep 25, 2004 Posts: 4359 Location: Boston, MA
Posted: Wed Feb 27, 2008 10:37 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
Trains can be electrified. Ships are extremely efficient users of oil when it comes to mass transport (even if we only produce a million barrels of oil a day, all of that oil will go towards aircraft and ships because those are the most efficient users...and we are centuries from that point) Tractors can be battery powered.
But again, food isn't the problem. We use relatively little oil in order to make all of the food we need. Food prices will go up in response to higher oil prices. Westerners will eat healthier (less energy intensive red meat), Sub-Saharan Africans will suffer, celebrities will hold fund-raisers, life will continue as normal for the people with access to potato chips and chewing gum. (top third of the planet)
It's transportation that's the problem. We have to restructure our society to use mass transit and rely less on individual random movement.
As for technology being the answer:
Look at that chart carefully. We have bigger refrigerators using less energy for a cheaper price per unit than ever before in history.
And yet we use more energy refrigerating food than ever before. Why? Because energy is cheap!
If energy becomes expensive, we will change our behavior. Coal is still well below the record prices reached in 1980. And considering that coal is used for half of our electricity...we have a ways to go before people are going to start conserving electricity.
I know this sounds like rambling but you're asking a lot of questions at once.
As for carrying capacity, I cannot pretend to know the answer to that question. My guess is that we are probably in overshoot or will reach that point in the next decade. As a result, people in overpopulated undeveloped countries will die off.
I look at it like the potato famine in Ireland in the 1840s. The British were well fed and purchased as much food as they wanted from Irish landlords. The Irish peasantry starved. But the chaos in Ireland didn't crash the British Empire. _________________ "www.peakoil.com is the Myspace of the Apocalypse."
Posted: Wed Feb 27, 2008 10:56 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
ekaggata wrote:
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.
Solar available? Just waiting to be used?
All solar energy that strikes the earth is either re-radiated into space or consumed by living things or systems.
There is no realistically available solar energy that doesn't involve taking it from some other system or organism. Human populations have repeatedly taken over for human use portions of the earth's total life-supporting capacity that had previously supported other species.
For us to have more solar appropriation something else has to do with less.
This is called the "take-over" method as opposed to "drawdown".
Posted: Wed Feb 27, 2008 11:03 pm Post subject: Re: Is Solar Power a Perpetual Motion Machine?
ekaggata wrote:
Think carefully about this. The first sentence asserts overshoot.
Overshoot is a given.
Quote:
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.
No, because it could never be a sudden, heretofore unaccessible energy/food source that would cause exponential growth of the population.
Quote:
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.
Like I haven't? You don't read my threads on population and overshoot? My reason for saying 2 to 3 billion is because that is what the leading experts tell us. _________________ 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.
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