Funny thing about energy: it’s conserved! At least when the spacetime background is time-translation invariant, which is a very good approximation here in the Solar System. We bring you this reminder because a knowledge of basic physics can occasionally be helpful when formulating public policy.
In particular, biofuels (such as ethanol) and hydrogen are not actually sources of energy — given the vagaries of thermodynamics, it costs more energy to create them than we can get by actually using them, as there will inevitably be some waste heat and entropy produced. Almost all of the useful energy we have here on Earth comes ultimately from nuclear reactions of one form or another — either directly, from nuclear power plants, or indirectly from fusion in the Sun. There is of course direct solar power, but even fossil fuels and biofuels are simply storage systems for energy that can be traced eventually back to sunlight. The question is, what is the best way of capturing and using that sunlight — where “best” is going to be some interesting function of cheapest, cleanest, most easily transportable, and most sustainable.
People seem to be gradually catching on to the fact that biofuels are an especially wasteful and dirty energy storage system. Paul Krugman devoted a column the other day to how ethanol is a boon to Archer Daniels Midland, but terrible for the world’s food supply. (We told you the Farm Bill was a travesty.) And Time has published a cover story on the “Clean-Energy Scam.”
Propelled by mounting anxieties over soaring oil costs and climate change, biofuels have become the vanguard of the green-tech revolution, the trendy way for politicians and corporations to show they’re serious about finding alternative sources of energy and in the process slowing global warming. The U.S. quintupled its production of ethanol–ethyl alcohol, a fuel distilled from plant matter–in the past decade, and Washington has just mandated another fivefold increase in renewable fuels over the next decade…
But several new studies show the biofuel boom is doing exactly the opposite of what its proponents intended: it’s dramatically accelerating global warming, imperiling the planet in the name of saving it. Corn ethanol, always environmentally suspect, turns out to be environmentally disastrous. Even cellulosic ethanol made from switchgrass, which has been promoted by eco-activists and eco-investors as well as by President Bush as the fuel of the future, looks less green than oil-derived gasoline.
As an uneducated guess, I would imagine that in the medium run the world will have to turn to (Earth-based!) nuclear power for its energy needs. In the longer run, solar will be the way to go, although the amount of solar power we can reasonably collect here on Earth is somewhat limited. We’ll likely have to solve the problem of how to efficiently beam power down from orbit, after which we can build big million-square-kilometer solar power collectors in space. Not in my lifetime, I would bet.
Eventually the Sun will run out, of course. But there are other Suns. In the even longer run, once all of the stars have run out and we are all virtual processes running on a computer, perhaps we can tap into the Hawking radiation from the supermassive black hole at the galactic center. Once that is gone and the universe has settled into empty de Sitter space, we’ll be in thermal equilibrium. At that point there’s probably little hope, no matter what optimists like Freeman Dyson might tell you.
Carl – the link for your “plant”? (factory) was empty.
Some observations and questions from an increasingly ancient non-scientist:
I have trouble understanding how the energy problem can be rationally discussed in isolation without careful consideration of the economic and social ramifications of various alternatives. While I recognize how difficult such considerations are, if there is such a discussion I have not seen it and would be pleased to have a reference.
My sense is that fossil fuels (natural gas, petroleum and coal in order) currently remain the most efficient way to use stored solar energy and at this point, the most efficient way to produce any energy. Is this an accurate assumption?
Another sense is that in the short to intermediate term increased efficiency in energy use can have the largest and surest favorable impact on energy sufficiency. Further, I suspect that much of the technology to pursue this path already exists. Is this reasonable?
Can increased efficiency in combination with attention to better control of the adverse effects of carbon based energy buy enough time to explore future alternatives in at least a semi- rational manner so that proposed saviors like bio- fuels can be thoroughly vetted before creating a bandwagon?
Thanks for the site and participants. I always enjoy following these discussions while marveling at the opportunity to do so.
M. Simon:
The technological feasibility of fusion isn’t really relevant- yet another way to produce energy at 90c/kWh isn’t going to help anyone. The problem with fossil fuels is not that they are the only source of energy. It is that they are the cheapest, as long as fossil fuel burners are allowed to release harmful combustion products into the atmosphere without paying for the damages that these waste products cause.
Carl: I suggested last year that using oil crops for biodiesel and sugar for ethanol would have a positive impact on diets, by making unhealthy food more expensive.
Seems to me energy is a problem that is here to stay, no matter what technology is used – until humanity figures how to balance its population’s impact to be less than the planet can naturally regenerate.
Simply put, we just have too damned many people on this island we call Earth.
George–Instead of relying on the kindness of strangers perhaps you might reconsider your own reasoning. Anne’s scenario (#8) requires burning of two liters of fuel (oil or ethanol) to produce one liter of ethanol. You (#13) wish to provide “Another way to interpret” this, through producing three liters of ethanol from corn or sugar cane, then selling one of them, and using the other two to produce more ethanol. (Hints: how many liters of fuel will you need to purchase to produce those three liters? After you sell one, how many more liters can be produced from the two liters left? What is the comparison of the initial fuel input to the fuel produced?)
Originally I thought it might be your version of reality that needed reconsideration rather than your reasoning. After reading the intervening comments I’ve tentatively, and somewhat reluctantly, considered the possibility that your reality may not deviate significantly from the spectrum of the population.
In the US you could build geothermal powerplants. They can actually be build anywhere, but in the US you have a lot of volcanoes so it is more easy to make geothermal energy them competitive with coal fired powerplants.
The magma underneath Yellowstone alone can power more than 1000 gigawatt powerplants for one century.
Count Iblis, why is there a time limit to the geothermal power plants you propose in Yellowstone?
Also, you want to build something like that fairly near Yellowstone, not in it. That would spoil the national park.
Pieter, below Yellowstone there is magma chamber containing about 15,000 cubic km of magma. It is located about 6 km below the surface. So, there is a finite amount of energy. If it is depleted you have to wait until new magma (perhaps produced by a mantle plume ) enters into the magma chamber.
Ah, OK I thought the magma under Yellowstone was in direct contact with the rest of the mantle. Makes sense.
If it is not energy does not grow on trees, then what is it that does? Why do you eat an apple if you get no energy from it?
The truth is, trees throughtou the world produce energy at 1000x faster pace than the menkind is able to consume from all fosil sources. But the environmentalists insist that it should be wasted by rotting rather than harvested by logging and farming.
And the trees could produce the energy at a faster rate, if they had more food in the air than the current 1/2500 CO2 contents currently available. But the enviromnmentalist will not alow you to double the CO2 levels.
Of course, you could keep the trees starving for CO2 food and rotting in waste as the environmentalists wish, and use the energy in the cleanest and leanest, original nuclear form, but only try to build a new nucelear plant and the environmentalists will shoot you.
In the retrospect, the environmentalists are the worst enemies of the mankind and all of its environment.
Petrus, first of all environmentalists fully realize that trees growing and dying (whether rotting or being burned) are part of the surface carbon cycle, which does not add to the total in the atmosphere *as long as the storage mass of plant matter stays the same.* But dragging old carbon up out of the ground adds more carbon to the above-ground system, that is the dangerous thing. Indeed, burning vegetation or its byproducts (such as biodiesel) is exactly what most environmentalists prefer. But for that to have a net benefit requires that we don’t destroy more plant matter than we grow. The reason environmentalists (really, a type of scientist, not best defined as a political faction) oppose burning lots of trees is the fundamental principle of replenishment versus new growth. If the net amount of plant matter keeps going down due to deforestation etc, then two things go wrong.
First, the equilibrium between solid plant storage and the atmosphere tilts towards the atmosphere, and more CO2 appears in the latter (that would happen even *if we didn’t* drag more up out of the ground.)
The second thing that goes wrong is, less O2 is produced by the remaining plant mass. It could take a long time, but if we destroy too many plants then our O2 concentration will start going down. People and animals can adapt of course (it will be like adding so many feet of elevation to your location), but it reduces total habitability and the productivity of the biosphere.
I really get irked when people who aren’t well versed in the relevant science make blowhard, defamatory remarks about how awful environmentalists etc are. It just fits in with the whole right-wing know-nothing radio and faux news culture, doesn’t it?
BTW I am OK with nuclear as long as its done competently and we get a good handle on how to deal with the radioactive byproducts (assuming we can.)
delver23
I heard in a lecture that if all of the good farmland was purely devoted to growing biofuels it would not be enough to sustain current demand. the fact is current technology is not where it needs to be, but that will change with time, as new research is conducted. I think the problem is politicians who think they know a little science overstep their bounds and make outlandish claims about the necessity of biofuels towards global warming (climate change is far more dynamic then simple warming and cooling) just so they can win a few more votes.
Neil B.,
I would vouch to “support” your arguments with some numbers. Namely atmospheric O2 concentration (19%) is 500times the CO2 concentration (0.038%). You would need to increase CO2 concentration 30.48 times to 11578ppm to reduce O2 down to 18%, an equivalent to ascending to 800m (2700′) elevation. Unfortunately, the current biosphere barely contains enough carbon to facilitate such increase. You would have to kill and burn 93% of all living matter, and do that quickly. Because the oceans, which already contain 50times atmospheric CO2 and still are just about half full will have your CO2 increase for lunch.
So when we look at the numbers, that ‘dredfull’ O2 depletion isn’t even an argument.
Talking about lunch, I hope you realize that no matter what form you eat your carbohydrates, they are mostly last year’s CO2. And unless you continually sequestering them in surplus tissue, with each exhalation you ‘pulute’ our air with 4.9% – that is 49000ppm(!) – concentrated CO2 gas.
If you really get so agitated by undereducated conservatives (as much as me), please take due care to edify yourself to the point that you can make some of these basic calculations for yourself and do not have to rely on others explaining them to you. Because otherwise you might be easiliy duped – as you probably are – into believing even nonsences such as impeding Global Warming Catastrophe and caused by – of all gases – by manmade CO2!
Irony aside, what I seriously propose is to get as much carbon as possible from the fosil fuels and facilitate aerial distribution via CO2 (BURN IT!). That’s because the highest detriment to increase in rate of fotosynthesis (of both food and biofulels) is the ridiculously small partial pressure of CO2 plant food (
…Continuatiuon from where the web SW cut it:
…the highest detriment to increase in rate of fotosynthesis (of both food and biofulels) is the ridiculously small partial pressure of CO2 plant food (
…Continuatiuon (web SW did not lile brace+greater_than)
…the highest detriment to increase in rate of fotosynthesis (of both food and biofulels) is the ridiculously small partial pressure of CO2 plant food ( ~38 Pa!) that the currently slow growing plants learned to starve on.
If we can increase atmospheric CO2 over 1000ppm, we will dramatically increase produce of both food and biofuels. But until we mine or drill all the necessary Carbon and throw it into circulation, biofuels will likely be a net energy loss.
Petrus – the issue with O2 depletion isn’t a matter of its amount relative to CO2 anyway. It has to do with how much O2 is produced by plant life versus the consumption by animals and plants (and include ambiguous microorganisms as well), not the direct conversion of O2 into CO2 (although that is part of it.) For example, if photosynthesizing plant matter is reduced to 1/2 of the previous amount, then the outflow of O2 to the atmosphere is about 1/2 what it was before, but if there are still lots of animals around (biologically, that includes people) then consumption outweighs production. Then, if we burn lots of fuel that reduces O2 even more.
Just consider equilibrium: d(O2)net/dt = d(O2)in/dt + d(o2)out/dt [where the loss, “out”, is negative to begin with, so we can add it to the first term at right.] Note that CO2 concentration or changes don’t appear directly in the equation. Look, we could be burning boron compounds and not even making more CO2, but their burning would still pull O2 from the atmosphere (and it would have nothing to do with how much boron oxides are in the atmosphere to begin with!)
Also, I don’t think plants are “starving” on the current 420 or so ppm, after all they were used to about 285 ppm for millennia and did well enough!
As for conservatives, well I can respect notions of e.g. adhering strictly to the constitution. But first, beliefs like that are no logical reason to doubt or be careless about atmospheric science. Second, what about the recent tendency of “conservative” administrations to wage war without declaration from Congress, overrule state laws by federal decree, extra-legal detentions, all that pork and indulgence of special tax breaks against the whole “simple and flat” tax idea, etc?
PS: As I already alluded to, what we breathe out is part of the recycling CO2 above-ground cycle and does not add to net CO2 anyway, yet uneducated or deliberately deceptive manipulators like Rush Limbaugh keep bringing up that thing about exhaling.
MedallionOfFerret writes #55:
I appreciate your comments, though am somewhat perplexed by their tone (and indeed by the tone of other comments on this blog — I worry that Cosmic Variance is starting to go the way of other blogs in shedding more heat than light). Perhaps, before you comment, you might find it instructive to look at the entire thread of thought. My original comment came from the observation that news stories are not very clear when they say that “it costs more energy to create them [biofuels] than we can get by actually using them”. What exactly does this mean? *Every* fuel requires more energy to create than it releases during use. At face value, all this statement really says is that the efficiency of a fuel is less than 100 percent — which is a trivial statement. If the energy comes from sun, it doesn’t really matter what the efficiency is (at least not for energetics — obviously it makes a difference for land use).
Anne then suggests that this statement might be interpreted, in effect, as “it costs more energy IN THE FORM OF LIQUID FUEL to create biofuels than we can get by actually using them”. That is a stronger statement than the original, as I was trying to get across in the post that prompted your remark about the kindness of strangers.
All I am really asking for is a detailed accounting of the energetics of biofuel production.
George
Neil B.
Please do understand my argument. The d(O2)net/dt = d(O2)in/dt + d(o2)out/dt only works with 1% of the atmospheric O2. There is not enough unoxigenized Carbon to bond with any more of it above ground, and much less of boron, sulfur, phosphor or other elements. Most abundant elements such as H, Si and Al are already fully oxygenated!
If you burn everything you can (except quite intert N), at least 17% of oxygen will still remain.
Moreover, you 1/2 vegeration argument is wrong. If you consume (burn, rot or eat) 1/2 of photosyntesis matter, you will increase the atmospheric CO2 3.5 times to 1400ppm. at 600ppm most plants photosynthesise between 30% to 200% faster. At 1400pm most plants at least double their growth. THATS why I am saying that thte plants are starving for CO2. They did live on 285ppm in the past, but all the huge deposit of coal and oil come from the house size ferns in Perm and Carbon eras when there was up to 5000ppm of CO2 in the air.
Why we cannot produce such a quantity of biomass nowdayws? It is not lack of water or lack of sunshine, these remain about the same. It is the lack of — CO2 !
RECLAIM THE LOST CARBON BACK OUT OF THE GROUND !
Correction:
The d(O2)net/dt = d(O2)in/dt + d(o2)out/dt only works with 1% of the air, and 5% of atmospheric O2.
BTW, I hoped that you would read my post, understand it, recalculate it and found some real mistake. Please do the effort, I do not mind to be proven wrong as long as your corrections are valid. But at this point, I see no essential flaw in my numbers.
I found that a small correction for mass of Carbon is needed in:
You would need to increase CO2 concentration 35.94 times to 13656ppm to reduce O2 down to 18%, an equivalent to ascending to 800m (2700?) elevation.
Neil,
To correct your calculations:
if photosynthesizing plant matter is reduced to 1/2 of the previous amount, then the outflow of O2 to the atmosphere is about 1.2 times what it was before due to increased photosynthesis rate on a 3.5x increase of CO2 partial pressure to 140Pa.
And as for politics, I do not subscribe to the neocnservatism. That is a betrayal of true conservatism and a dangerous way leftward to National Socialim.
http://www.telegraph.co.uk/money/main.jhtml?xml=/money/2008/04/14/ccview114.xml
Return to math. When given a problem one finds that multiple approaches yield the same solution. Good for checking. Hurray! Return to Physics. Good old Feynman pondered that wave hitting all pathways really returns one and only end result.
Lesson to be learned. The solution is about bundling if the general result is to be the same. Something that the market speculators are so experienced in.
All solutions have + and – outcomes. The best that you can do is offset the – of some with the + of others. Rather than concentrating and promoting one less + and more – solution, or one more + and less – solution. Imbalance is a bad game. Equilibrium rocks.
When will politicians and scientists wake up to understand that.
Petrus and whoever is reading, sorry for the late followup. I do not see any scientific basis given for Petrus’ counter-intuitive calculations and claims (Sorry, whether it seems fair or not, the burden of proof is on the counter-intuitive claims that contradict what we expect simply and straightforwardly to happen.)
Neil,
I undeiably refuted argument, that suggests that:
“Increase in CO2 can substantialy reduce O2″ .
Essentially because the whole biosphere does not have enought C to match O2 into CO2 molecules (Can match only 5% of O2, calculated with abgout +/-10% accuracy)
Moreover, I refuted argument:
” 1/2 photosynthesizing plant matter reduction (by byrning) reduces outflow of O2 to the atmosphere by 1/2 ”
Because this naive calculation overlooked 2x to 3x increase in photosynthesis under highger CO2 concentrations.
You did not point to any mistakes or omisisons in my detailed calculations posted above and that suggests that you do not have sufficient insight to debate them. Sadly, over again I find this the problem with environmentalists, that while undereducated, they presume to possess higher knowledge. But even during introdudtion to the scientirfic tenets of the theory they soon betray their inability to follow, let alone counterargument.
Why you might have lost this argument, I appreciate your honesty and willingness to study the subject. The proof seems to be self evident but I would be every glad to present clarification. Please point constructivelly to the specific staements that are unclear to you so that I may elaborate on them.
Pingback: Global warming is a loser and I will kick its ass « The Poor Man Institute