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.
I’ve always been confused by the debate over biofuels. For instance, consider the statement:
Why should this matter if the energy is coming from the sun, anyway? All this statement seems to be saying is that the fuel efficiency is less than 100 percent, which is hardly unique to biofuels. The real concern is that the production of biofuels might consume more fossil fuel (through fertilizer, tractor fuel, transport, etc.) than it displaces. Even this particular problem, though, could be solved by using biofuels themselves for the inputs.
George
I think there is an important conceptual difference between thinking of ethanol as “a battery” instead of “a fuel.” Of course petroleum and coal are also just energy-storage systems, but we don’t make the choice to create them; they’re already there. (Not that I’m advocating fossil fuels as the solution to anything.)
If people think of ethanol as “a way to store solar energy in the form of corn” rather than as “a source of energy,” the costs will make more sense. Many non-scientists aren’t trained to think of it this way, so it’s worth emphasizing the point.
The real questions, undoubtedly, come down to cleanliness and efficiency etc, as I said in the post. But on those measures, biofuels do badly.
It depends on your reference point. Biofuels may do badly compared to solar panels, but compared to oil out of the ground, they seem a distinct improvement. The debate really revolves around other issues such as food prices and land conservation — not the energetics.
I’m not sure the parallel between biofuel and fossil fuel is shedding much light. The question is whether a given energy source is a net addition to atmospheric CO2.
George
No no! We will then escape into the past and destroy Japan! We need to get cracking on that Paradox Machine!
The key thing to remember is that there are more issues at play in finding “alternative fuel sources” than being “green”.
Specifically the fact that oil is going to run out, in the short term. And also the dependence of our nation on foreign countries to supply the literal and figurative “fuel” for our economy.
Those questions AND environmental concerns COULD all be answered by a single alternative fuel source, but they don’t necessarily have to be. It is possible to answer any or all of those questions separately using different approaches which may or may not address the others.
Renewable
Domestic
Clean
These issues are not the same, although they can potentially have the same answer.
I have pondered the way of Cosmic Wind-Turbine Energy?
..if http://en.wikipedia.org/wiki/Wind_turbine could work on a ship sailing the oceans (wind-turbine propelling ships instead of diesel or sails)..then it seems a natural progression would be to have a facility orbiting a country, storing energy, and transporting it down to Earth, via entanglement maybe?..or space-shuttle cargo hold sized rechargable batteries?..plugged directly into the Cosmic wind!
“Eventually the Sun will run out, of course. But there are other Suns. […] 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”
This is the theme of Isaac Asimov’s famous (and his own favorite) short story, “The Last Question”.
@George Musser:
Suppose you have to burn two liters of ethanol to produce one liter of ethanol, and suppose, for the sake of argument, that a liter of oil and a liter of ethanol are equivalent. Then there’s no way you can run on pure ethanol: If you start with a million liters of oil, you can produce only half a million liters of ethanol. But you can’t just burn that ethanol, you need some to produce more ethanol. If you keep all of it to make more ethanol, you only get a quarter million liters of ethanol; if you sell some of it to SUV drivers, you make even less ethanol in the second generation. The third generation’s problems are even worse. It’s like using one battery to charge another: it works, but you lose some. If you then use the second battery to charge the first, you’re behind where you started. This is what agrofuel opponents are claiming occurs.
Then, too, there are the problems of agriculture: it can be extremely hard on land, requiring large amounts of fertilizer and destroying wild land cover. Jared Diamond’s book “Collapse” argues persuasively that deforestation is a more serious environmental concern than global warming (and he thinks global warming is pretty serious). It is responsible for much of the mass extinction we are producing. An increasing amount of agriculture can be very destructive.
That said, I have long wondered whether there isn’t some kind of plant that can be grown on salt water in desert areas and burned for fuel. Carbon-neutral, in principle, and using only land we have already made barren. Unfortunately things like the sulfur in salt water pose serious difficulties to this plan.
Tap into the vacuum enrgy. Casimir effect ? If I remember rightly NASA was handing out some seed research grants on that a few years back.
Ethanol catches hell from the right wing because it is supported by government mandates and it catches hell from the left wing because it is industrial. And the extreme greenies publish the most amazing crap that gets repeated by the media because it is of human interest in the sense of “Man Bites Dog.”
Our plant in Moses Lake uses barley. Barley is grown without irrigation water on dry land that would not otherwise have a crop on it. We’re not starving the poor and we’re not using more energy to create ethanol than we’re burning.
The concept that agriculture, which is only a tiny fraction of the US economy, is driving prices higher is ridiculous. A bushel of corn still costs under $7. That’s 14 cents per pound. It’s not contributing much to food prices. Food (and everything else) is up 15% in price because energy is up 100% and transportation is about 25% of US GDP. It’s $112 oil that is running prices up and ethanol helps reduce that.
Brazil has almost eliminated its use of oil as transportation fuel by using ethanol. They make it from sugar cane because that is the most efficient way currently to do it. The US is a colder climate and we can only get about 2/3 as much ethanol per acre as Brazil but we are still the world’s most efficient corn producer and our corn is nearly as efficient as sugar cane. The difference is largely in the fact that the waste product of a sugar ethanol plant is burned for energy while the waste product of a corn ethanol plant is fed to cattle (as a partial replacement for the feed corn).
Economically, one bushel of $6.00 corn will make 2.9 gallons of $2.50 ethanol and 1/3 bushel of “distiller’s grains”. The distiller’s grains replace corn, so really what you end up with is $4.00 worth of corn making $7.25 worth of ethanol. That’s right, even with the subsidy ethanol is much cheaper than gasoline. And if it took more gasoline than $7.25 to grow and transport a bushel of corn, then how the heck do they sell corn so cheap? The guy who wrote the scientific papers claiming otherwise is a nitwit who is well known for his other bizarre left wing political beliefs.
For the real story on ethanol, read “Energy Victory” by Zubrin.
I’m not sure you can claim that tidal energy comes from nuclear reactions. It comes from the angular momentum stored in the mass and velocity of the Moon and Earth, which in turn comes from … what? The Big Bang? Was that a “nuclear reaction.”
Energy sort of DOES grow on trees.
I’ve got a whole pile of pollarded Ash that burns quite nicely in the Multi-Fuel burner and just grows back again in a few years. But I’m not suggesting that this could heat everyone’s home.
One point though, regarding growing any form of cereal crop: –
The growth in agricultural production over the past 50 years has been dependent on nitrate fertilisers.
Current world production is over 100 million tons per year.
Almost all of it comes from the production of Ammonia using the Haber process, almost entirely fed from natural gas and coal.
So in the long term, it might make sense to concentrate on nitrogen fixing plants as a source for both bio-fuel and animal feedstocks, rather than Maize.
Lupins anyone?
Anne (#8): Another way to interpret the “it costs more energy to create them than we can get by actually using them” statement is that you grow enough corn or sugar cane for three liters of ethanol, two of which are then used for ethanol production and one is sold as fuel.
I agree with you that issues such as deforestation are pivotal here, although things do change somewhat if we’re talking about cellulosic ethanol, which is produced using plant waste and therefore can be a byproduct of food production.
There is a lot of lazy language in this entry that detracts from the conversation.
Actually, anything with mass is a source of energy, since e=mc^2
More to the point, biofuels are a storage media for solar energy. The “cost of production” is the amount of energy necessary to prepare biofuel to release its energy, analgous to the initiation energy needed for many chemical reactions. Nobody who has ever lit a firecracker knows that the initiation energy releases much more energy than initially required.
This of course is not necessarily the case with biofuels. Corn for example has a very high water content – to prepare the corn for use in an industrial furnace a lot of water needs to be evaporated, which is an expensive process. Much of the frustration with the biofuels issue is the way industrial corn producers have hijacked the topic away from fuels that require much less energy to prepare, leveraging political power in pursuit of another market for their product.
A nuclear power plant here on earth presents a number of challenges, including significant questions of how to handle nuclear waste. The sun, despite being highly radioactive, happens to be several million miles away, and its threats are fairly well known and primarily in the ultraviolet and infrared bands (at least on the earth’s surface).
A more accurate comparison might be of biofuels to petroleum products. Both are plant-based storage of solar radiation. Petroleum has the advantage of several million years of geothermal heat and pressure increasing the concentration of energy per volume. If we had several million years to work with, we could grow crops of almost anything and come out with petroleum at the other end, too.
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.”
This conflates the frustration of the hijacking of the biofuels movement by the corn industry with the extremely early state of biofuel technology. How clean were the coal and oil industries when they were only a decade old? The denial-motivated hand of the oil industry can be seen behind such major-media concern-trolling by Time and other large media.
Terms like quadruple and quintuple can suggest overinvestment, OR one can realize that the industry was so small to begin with that very little is required to increase investment by an order of magnitude.
Studies paid for by which oil industry, one is forced to wonder, since the studies themselves are not named. And, again, how early in its life is biofuel technology?
More to the point, what should we then do? While wind is certainly a valuable alternative that needs to be explored, the nation has sufficient resources to explore more than one path at a time, and prudence suggests not investing all our R&D eggs in one basket. Even before oil runs out, the need for our petroleum-addicted nation to escape the influence of its foreign suppliers is amply evident. It is critical that we find alternate energy sources, and this will involve research to improve technologies by making them cleaner and more efficient.
We don’t have until 2050 or 2075 or whenever you were planning on perishing in order to find alternative fuels, hence the need to explore and research.
I’m going to risk being un-PC here, and say that this is a problem that I’m willing to leave to my offspring..
Sigh. Biofuel is not in all cases equal to corn-based ethanol. The current thinking in the media seems to be: biofuel = ethanol, ethanol = corn, corn takes a lot of fossil fuels to produce, therefore biofuel is dumb, QED.
Yes, biofuels are just a storage medium for solar energy. Compare it to to the alternatives for this conversion/storage: electric batteries and solar cells. Solar cells now get better conversion efficiency than most plants do, but then you have to store this electricity in some usable way. You can spend tens of thousands for an efficient battery pack to store this electricity for running your car, as long as you also have the electric motors and control systems for your car and you never drive too far from your acres of solar cells (which aren’t cheap, and hey, you can’t plant food under them), or know where to charge on the road.
Or, you can plant an oil crop, spend a couple hundred on barrels and filters, and run your old diesel car on the result.
So how much fossil fuel in the forms of fertilizer, plowing, mechanical processing, etc, do you use? Well, if biofuel = corn ethanol, a lot. If, on the other hand, it’s biodiesel from canola, planted on a farm in Oregon, practically nothing, the stuff grows like a weed and pressing it is not that energy intensive. I personally know of a farm in Oregon that plants a small portion of its land in canola and runs the entire farm on the biodiesel. The tractors, the oil presses, the harvesters, the pickup trucks, the backup generator. (I’ll post a link if I can find it later). This is a working farm, growing many other crops, and they are profitable – which would not be possible if it cost more economically or in terms of energy to use biofuels over fossil fuels. Oh, and it’s carbon neutral, and they produce quite a bit of other food.
My point is this – Biofuel != corn ethanol. It can be a very economical system for converting solar energy into easily transportable energy that works well in the current liquid fuel infrastructure. Until it is economically possible to run our cars on batteries, and solar cells come down to the cost of canola seeds (or nuclear becomes socially acceptable), biofuel is the best carbon-neutral power system we’ve got for many uses – vehicles in particular (you can even run jet airplanes on a form of biodiesel). Sure, electric cars, efficient solar, safe nuclear, wind, waves and geothermal would give us much better efficiency, would be cleaner, easier, and all around better – but they aren’t here right now, and biofuel is.
Corn ethanol deserves a harsh look – any new “fuel” does, and the end-to-end analysis that includes environmental damage, total fuels usage for the entire production cycle, subsidies, food supply, etc, is clearly important. But don’t look at what ADM and the big agro-corps are pushing and assume that is what biofuel -is-. Don’t throw the baby out with the ethanol.
Sean
Nuclear fusion deserves a mention here. At a talk last year, Chris Llewellyn-Smith, director of UKAEA, made convincing arguments for commercial fusion plants in 30 years, producing no isotopes with half lives greater than 10 years (see Fission Impossible).
At the end he was asked an interesting question. If the next US president has a JFK moment and sets us the goal of making a viable fusion plant in ten years, could it be done?
Man, lotta typos of my own in there, sorry – short on time today.
c/Nobody who has ever lit/Anybody who has ever lit/ etc etc
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,
If any small part of us, or our technological descendants, ever survive to this point, they’ll have long since figured out a way to to exit this universe and/or create their own new one. And out of hundreds of millions of galaxies and billions of years, it is utter hubris to assume that we are the first and only forms to even contemplate the question, and that other forms wouldn’t have, say, a few billion years lead on us…
We don’t have billions of years; we don’t have centuries. We might not even have decades. Jesus is coming back, and Time will Stop when He’s finished.
George depends on the kindness of strangers.
Jesus is coming back, and Time will Stop when He’s finished.
Well, I sincerely hope this time he can manage to do something a bit more useful than getting himself tortured to death, or starting even more crazy religious sects and wars.
Sean,
I agree with the assessment medium term nuclear, long term solar. However one other “bio”-fuel is intriguing and that is algae. Not in competition with food supply and very high yields per acre. I would also consider this transitional, like nuclear until solar is there.
The other issue with solar to electricity is storage. Batteries are heavy and inefficient. Thats why I am thinking algae based bio-fuel, either biodiesel or xxx-onol (not necessarily ethanol) for transportation.
That’s my two cents.
Regarding nuclear waste folks. Go google around and find the total volume of all nuclear waste. I’m not saying it is not a problem but the answer will surprise you.
e.
I’m hoping for fusion together with solar in the long term ~30-40 years.
Nuclear is fine for near short term, but will require a certain amount of government involvment to bypass all the redtape. As it stands eco organizations can successfully stall a nuclear power plant for 10 years or so in legal battles and permit battles. Only a broad bipartisan mandate can push that through to sensible timeframes
The other issue is its still damn expensive in terms of capital costs so really does require some strong backing.
But by and large the energy problem is not really a western issue. We will cope with it just fine in our lifetime. The major problem is for developing countries with exploding populations and high GDP growth. They will invariably have their growth severely stunted as a result of power shortages and this conflict could very well lead to wars in the future.
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.
…what? Time doesn’t back up this statement– with anything— and this doesn’t exactly mesh with the data I’ve seen.
Just… ugh. I’ve seen a lot of deeply flawed advocacy for biofuels lately. But this article seems to take all the sins of biofuel hype pieces and invert them neatly– this article considers biofuels an unambiguous evil rather than unambiguous good, but is not actually any more honest. The article buys into the basic fallacies of ethanol hype: that biofuels have to be either all good or all bad, that all biofuel sources are created equal, that all we have to do on biofuel policy is pick a “for” or “against” and not worry about the details.
Biofuels have the potential to be an invaluable partial solution to our energy problems. They also have the potential to be a confusing waste of resources, consuming as much or more usable energy than they produce. Biofuels also have unique pitfalls clouding any attempt to judge which of these two things is happening, for example because it is difficult to accurately measure the energy and environmental costs of agriculture. What we need to do if we are to use biofuels is have a sober reckoning of what our options are on biofuels and what the costs and benefits of those options are. But I don’t think we can be moved toward such a reckoning by any analysis that can’t separate biofuels-as-a-concept from particular biofuel production implementations, or which treats corn/sugar/switchgrass/etc as interchangeable. Even where this article brings up important problems with modern biofuel production, it seems to do so to demonize biofuels in general rather than to point out there are things rather deeply wrong with some of the ways we’re making biofuels now. I don’t quite think the public education problem on the limitations of biofuels is really helped here.