Help Me Out, My Organic Chemistry is Rusty...

The Thin Green Line passes on an editorial from today's SF Chronicle:

California should continue to lead the way in the fight against climate change by requiring cleaner-burning fuels in this state.

The state Air Resources Board is scheduled to vote today on whether to force refiners and distributors to reduce the "carbon intensity" of the transportation fuels they sell, starting in 2011. The so-called Low Carbon Fuel Standard represents a critical step toward this state's commitment to reduce overall emissions of heat-trapping gases by a third by 2020.
Passage of a California cleaner-fuels standard would intensify the pressure on Congress to make a national commitment to promote lower-carbon options to gasoline and diesel.

Holy moly, I never thought of this?  It's brilliant!  Let's just legislate that hydrocarbons should have less carbon!  And tell the refiners to figure it out.

In all seriousness, assuming this is not just insane (which may be a poor assumption in CA) I presume they have something in mind here.  Does anyone know what opportunity they see, because I sure don't.  Here is why I am confused:

Basically transportation fuels are made up various hydrocarbon chains.  The shortest is methane, CH4, then C2H6, then C3H8, etc.  As the chains get longer, the molecule gets heavier  (for example, CH4 is a gas at room temperatures; C3H8 is propane, which is a gas but a liquid under pressure in our BBQ tanks; C8H18 is octane and liquid at normal car operating temperatures.)

Motor fuel is a careful blend of many different molecules, and is actually frighteningly complex (the above just discusses straight chain forms, there are also rings and other shaped hydrocarbon molecules).  There are literally hundreds of specs it has to meet, and several present difficult tradeoffs that must be carefully balanced.  Trying to make one spec can easily put one out of another spec.  So this is an optimization equation with a lot of constraints.

All things being equal, decreasing the carbon intensity of fuel basically means making it lighter, with shorter molecules.  Why?  Well, look at the molecular equations.  Basically a straight chain hydrocarbon is C(x)H(2x+2).  Shorter molecules get a higher ratio of their BTU's from combustion of hydrogen vs. larger molecules get a higher ratio of their BTU's from carbon.

So, it is correct that burning propane in a car vs. currently formulated gasoline will be less carbon intensive, with only the teeny tiny problem that most cars today cannot burn propane.  Modern engines are carefully built to run most efficiently (valve design, cylinder pressure and size, air mixtures, fuel injection)  on a certain range of gasoline, and that range is moderately narrow.  And, besides the pure physics of engine design, lightening up motor fuels will create a variety of secondary problems -- for example, lighter fuels tend to have higher vapor pressures and volatility that can cause vapor lock in engines on warm days.  Another way to reduce carbon intensity is to go from ring molecules (e.g. benzine) to straight chains of the same size, but this creates other problems, for example in maintaining octane numbers.

And speaking of unintended consequences, my understanding is that environmentalists like diesel engines, because the best diesel technologies today are far more efficient than gasoline engines.  But diesel is a heavier, more "carbon intensive" fuel than gasoline.  So is the carbon dioxide emissions from a heavier fuel in an engine that is more efficient less or more than a typical gasoline engine?  Who knows, and the answer is probably "it depends" anyway.

Update: I think I have figured it out.  The California legislature is going to mandate changing the size of the 2p valance shell, allowing more hydrogen molecules per given carbon molecule.


  1. Raymond:

    The problem is not your understanding of chemistry, it is your understanding of the bureaucratic mind. The state of California has mandated that all fuels sold in the state reduce their carbon intensity,measured in lifecycle carbon emissions/BTU.

    One way this can be done is by adding ethanol to gasoline, but only if the ethanol is grown and processed in a way approved by the state. So, if you grow corn, harvest it by hand, pull it to the processing plant in a wheelbarrow, and convert the starch to ethanol using sunlight you get a lower carbon intensity fuel than someone who harvests with a John Deere tractor, trucks the corn to market, and buys power for the conversion from an emissions-spewing coal plant. In fact, that ethanol might actually increase the carbon density of the fuel.

    Somewhere in the middle is the wise farmer who ships his corn on the river, which is less emissive than trucking it to the processing plant.

    If you use animals on your farm I suspect it would be necessary to keep detailed records of their feed so that the their flatulence can be added to the fuel emission.

    If you think this is ridiculous, wait until you see how cap and trade works.

  2. Fred Z:

    Man, you are looking at this the wrong way.

    Stupidity is a resource. Where there is plenty of stupid a mediocre guy like me can get rich competing with the stupids.

    Go west, young man!

    I'm going to California to open a stupidity mine. I'm a miner 09er.

  3. Stan:

    So Cali is legislating at a molecular level now. Awesome.

  4. Dr. T:

    "The state Air Resources Board is scheduled to vote today on whether to force refiners and distributors to reduce the “carbon intensity” of the transportation fuels they sell..."

    I was a chemist before I became a physician. There really are less "carbon-intense" fuels. If you increase the oxygen in hydrocarbons, then the amount of carbon per gram of fuel is lower. Unfortunately, the fuel is already partly oxidized and is therefore less efficient as an energy source. (In case you didn't know this, the 90% gas/10% ethanol blend reduces gas mileage by about 3%, and that's if you have a fuel injection system programmed to deal with gasahol. Unlike what California believes, gasohol does NOT have fewer CO2 emissions per BTU, it has fewer BTU emissions per gallon.)

    You can also substitute other elements for some of the carbon atoms in fuel. The commonest substitute is nitrogen. It burns almost as well as carbon, but it leaves behind nitrites, nitrates, and nitrous oxide which are nasty pollutants. Oops! You can replace carbon with sulfur, but then you get sulfur dioxide, sulfides, and sulfuric acid which are nasty pollutants and a major cause of acid rain. You can try phosphate, but, you get phosphates and phosphoric acid that also cause acid rain. Another way of lowering "carbon-intensity" is to add lead. I'm sure we'll be happy that our attempts to generate less CO2 damage the brains of our children.

    As usual the politicians and government bureaucrats are clueless and unconcerned about passing regulations that cannot be followed without changing the physical laws of our universe. Now if only we could send them to an alternate universe where less carbon means more energy...

  5. morganovich:


    just FYI- you don't mine stupidity out here. you farm it. (organically and sustainably) there is nothing underground about it. it grows as high as an elephant's eye. just sprinkle lovingly with a little bit of psuedo-scienficic/economic dogma and you get a bumper crop nearly every year. some if it may even be perennial.

    i would wager that you could get San Franciscans (and i live here so i have some direct experience) to sign a petition demanding a 20% reduction in wind resistance to make our existing cars get better mileage if you wrote "SAVE THE EARTH" on top in big enough letters. everyone knows that air friction is a stooge of big oil....

  6. Max Lybbert:

    I think the main push was natural gas (well, Raymond has a possibility as well). I understand natural gas is les carbon intensive; although like ethanol natural gas doesn't pack as much energy per gram so you end up burning more of it to do the same job.

  7. Bart Hall (Kansas, USA):

    Okay. Assume for a minute they go for it.

    The answer is di-methyl ether, easily refined from coal and well-suited to powering existing diesel engines with very minor modifications to adjust for the fact that it's a liquid only at propane-like pressures.

    DME also contains no carbon-to-carbon bonds and is consequently very "greenhouse friendly" if you ascribe to that particular pile of horseshit.

    The point is, DME is a fantastic way to flush people out on their *real* agenda. If it's really about reducing "carbon intensity" then DME is by far the best immediately applicable technology, and could almost completely power our entire truck and train fleet within about five years, along with an awful lot of cars.

    If they're unalterably opposed to COAL, and coal refineries, then you know their primary desire is to hamstring American progress, probably because they feel "left out" and wish not to confront the real reasons for their misfortune and failure.

  8. Flatland:

    The ether comment is funny. Replace reasonably stable hydrocarbons with a dramatically more flammable/explosive one. (Most ethers are considered one of the most dangerous common hydrocarbons.) After adding in all the safety features for the vehicles and infrastructure, the cost would be ridiculous. This isn't a rip on the comment, instead I agree with pretty much everyone that there is no good option.

    Before I read the comments I was thinking about Picken's plan to use natural gas. Living in MN, I can't imagine what that would do to the cost to heat my house.

  9. Fred Z:

    "you don’t mine stupidity out here. you farm it."

    OK, OK, I'll start a stupidity farm. Where do I get the seeds? Congress? Pelosi? Berkely? Downtown San Francisco?

    Do Democrats have a monopoly on the fertilizer or can I get some from a Rethuglican supplier?

  10. Kyle Bennett:

    "OK, OK, I’ll start a stupidity farm. Where do I get the seeds? "

    The major supplier in the state has a website:

    Avoid the ones produced by small, private manufacturers, and especially by people in their homes, they're practically unusuable for your purposes.

  11. DrTorch:

    Well, these are considered "Laws" of Thermodynamics, so it's understandable why the legislature believes it's w/in their purview.

    There is another issue that could be a factor, how much of the raw hydrocarbon escapes into the atmosphere? If using propane, then it's possible the seals let less propane into the air than gasoline (largely octane, heptane and EtOH). In fact gasoline fumes rank in the top 10 of contributors to smog in cities. And, the pure hydrocarbon is a worse greenhouse gas than CO2, b/c it absorbs more IR radiation, and small absolute changes in their atmospheric abundance are large relative changes (not so for CO2).

    All that being said, this is a hugely complex issue. One cannot ignore the cost (and that includes energy/polution cost) involved in changing autos and fuel distribution from gasoline to propane and/or methane. Then there is the need for production/refining. That means changing refineries, developing new catalysts, all to pull out short chain HCs from the long chains found in crude.

    I'm skeptical you'd ever reach a break-even point for such an investment.

    I'd much rather see progress in electric cars, like the Tesla!

  12. morganovich:


    the real coup would be starting a stupidity farm and then getting a federal subsidy NOT to grow any to keep prices high. sure, the recursiveness there might cause a stupidity singularity, but an attentive observer might counter that this has already happened so not to worry...

  13. LA Denizen:

    FYI, the CARB site says that it's measured on a GHG/BTU basis, so they already thought about your commentary about watering-down the fuel by adding ethanol.

    Reading through the technical documents, this appears to be a flagrant attempt to mandate cellulostic ethanol, since that is the only technology they list that has a chance of meeting the goal. Unfortunately, cellulostic ethanol is still 10 years away from working.

    The CARB site also suggests that electric vehicles might somehow count toward the goal. I'm not sure exactly how that would be counted toward a refiner's quota.

  14. Zach:

    This is what happens when we substitute psychology, sociology, and [victim_group]* studies for math and science.

  15. Bond in Michigan:

    I agree generally with the above comments. I have 15 years experience with oil refinery technologies. There are several major process units in a refinery that produce high octane material that are blended together to make the final product gasoline. One of them, Alkylation, produces a clean burning, relatively low carbon, high octane fuel. Catalytic Naphtha Reforming, CNR, most popular version Platforming, newest CCR Platforming, is less clean burning, relatively high carbon, high octane fuel. The product from the Fluid Catalytic Cracking Unit, FCCU, which is most of the gasoline blendstock pool is intermediate between Alkylate and Platformate in octane, clean burning, and carbon output. The difference in carbon dioxide production between FCC naphtha, alkylate and CNR naphtha is trivial. It is not technically possible to produce only alkylate in a oil refinery and not legally permitted for California refineries to import alkylate and export FCC naphtha and Platformate/CNR naphtha to other states due to "antidumping" laws in environmental legislation. California politics is stupid, crazy.

  16. Jim Collins:

    Actually this is a win-win-win for the morons in the California legislature.

    If the refineries happen to pull this off, they win

    If the refineries can't pull this off then they can fine them and use the money to reduce the State's debt.

    If the law happens to get struck down, they can tell the tree huggers that they tried, but the evil oil industry bought off the courts with their huge profits.

    Me personally, I'm rooting for the earthquake they call "the Big One".

  17. Keith H:

    "The California legislature is going to mandate changing the size of the 2p valance shell, allowing more hydrogen molecules per given carbon molecule."

    Hahahahahahaha! This reminds me of Patrick Moore, the cofounder of Greenpeace, describing one of the reasons why he ended up leaving the organization:

    "...while I was there...we should start a campaign to ban chlorine worldwide. I said, 'You guys, chlorine is one of the elements in the periodic table. I don't think that's in our jurisdiction.' And they said, 'No, this is a good campaign. Chlorine is the devil's element, and it works really well for fundraising and media and everything."

  18. DrTorch:

    I thought sulfur was the Devil's element.

  19. tomw:

    He said:"Shorter molecules get a higher ratio of their BTU’s from combustion of hydrogen vs. larger molecules get a higher ratio of their BTU’s from carbon."

    That means, when you burn H2, you get H2O. Water. The most common 'greenhouse gas' with multiples of the spectrum that it will absorb heat. I don't have the right words, but water is a muy worse GHG than CO2. Yet, everyone wants to burn 'clean' natural gas to generate electricity, which puts out much more water vapor.
    .035% CO2 by volume. .00035 of the atmosphere.

    Someone is truly smoking some good stuff... if they think that can have the effects described.
    The AGW or Climate Change group is losing the battle, but they will leave behind a legacy of legislation that will hinder society for years, and will be hard to reverse because of the "you don't want to make things dirty again..", i.e. "it is for the children" bleat.

  20. dr kill:

    You have the best readers in the blogosphere. Carry on, I might learn something.

  21. Mesa Econoguy:

    everyone knows that air friction is a stooge of big oil….

    That’s awesome.

    Except wind energy is supposedly powering California as we speak.

    Perhaps we should locate enormous rotating-knife turbines at the Capitol exits, like this

    [corporate commentary.]

    Just you solar energy nutjobs wait until Mr. Burns blocks out the sun....

  22. Mesa Econoguy:

    And, re: Update: I think I have figured it out. The California legislature is going to mandate changing the size of the 2p valance shell, allowing more hydrogen molecules per given carbon molecule.

    That will simply be met with heavy water (H3O) taxes, after H2O (vapor) spewing H-fuel cell vehicles cause a far larger problem, humidity increase every-freakin-where.

  23. Mesa Econoguy:

    Sorry, meant hydronium.

    Apparently, we have increased acidation to look forward to.

    Wasn’t acid rain one of the 1980s bugaboos…?

  24. Ned:

    There is another option - though it too is not very good.

    I think they are trying to push hydrogen cars. Hydrogen for cars is usually generated by stripping it from methane gas. What the companies do with the C after the H is stripped away, I have no idea.But yeah, the cars themselves will be use low carbon fuel.

    I don't think environmentalists actually try to think things through, and most people are too busy to figure out that their legislators are duping them.

    Pollution free electric cars, which caused GM to waste $2 billion are a good example. Sure the cars don't directly pollute, and are zero carbon but then there has to be some coal or NG powered plant which provides the extra energy somewhere. And then you have to pollution created trying to mine and dispose of Nickle used in the batteries.

    In the end though I could support a plug in hybrid or electric on the grounds that it will allow us to use domestic coal for power, and we will then have to import less oil from loony American hating countries overseas.