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Unforced variations: Sep 2012

Filed under: — group @ 5 September 2012

Open thread – a little late because of the holiday. But everyone can get back to work now!

591 Responses to “Unforced variations: Sep 2012”

  1. 201
    Ron R. says:

    Oh, one last thing.

    To transport the total sunshade mass of 20 million tons [16 trillion flyers and 20 million armatures], a total of 20 million launches will be needed, given flyer payloads of 1,000 kg.

    Sounds like a lot of resources.

  2. 202
    Rob Dekker says:

    Ron R,

    The technical challenges with the space “sun shades” project that you mention are probably only the tip of the ice berg.
    The author of the paper has considered many of such issues, and I am impressed with the level of detail in working out feasible technical solutions to the problem, but even from his story is obvious that many technical breakthroughs are needed before we could even begin launching such solar shades into space on such a massive scale.

    On huge assumption for example is that launch cost to bring payload into high orbit would be reduced from the current $20,000/kg to the $50/kg that is needed to keep the project within the $ 3 trillion price tag.

    The author’s closing notes are revealing in that sense :

    In conclusion, it must be stressed that the value of the space sunshade is its potential to avert dangerous abrupt climate change found to be imminent or in progress. It would make no sense to plan on building and replenishing ever larger space sunshades to counter continuing and increasing use of fossil fuel. The same massive level of technology innovation and financial investment needed for the sunshade could, if also applied to renewable energy, surely yield better and permanent solutions. A number of technologies hold great promise, given appropriate investment (3).

    My main point goes one step further : We do not want to get to the point where everyone on the planet agrees that “dangerous abrupt climate change found to be imminent or in progress”.

    My parents told me, and I tell my kids : “If you make a mess, you have to clean it up”.
    So far, there is ZERO cost to emitting GHGs.

    Instead, drafting geo-engineering plans gives us a sense of the cost of what it takes to clean up after ourselves. So carbon can have a price on it, which we can use to choose better alternative.

    Geo-engineering plans (as well as carbon-sequestration plans) may be one way to actually determine what the cleanup cost is for the mess we are making for our future generations.

    From my heart, I really hope that we as a species have enough “anticipation” capability and “discipline” to put a price on the risks that we are taking. Before it’s so late that we have to actually DO geo-engineering and solve all the problems that come with that.

    And then find out that we can’t fix all the problems.

  3. 203
    Ray Ladbury says:

    Jim Larsen,
    With all due respect, you are full of beer and beans. The oil counts for a minority of the cost. Processing of the petroleum is not free. Those plants are expensive–both to build and maintain. Look into the economics before spouting off.

  4. 204
    wili says:

    “A well drilled is a well pumped dry. The only decision point is before a single drop gets to market”

    Given what you’ve just said, the decision point would seem to be quite a bit earlier–before they start drilling, or even before they start prospecting.

    I think not enough emphasis has been placed on the supply side. We have to insist that corporations and countries stop un-sequestering carbon by pulling ff’s out of the ground, period. Start with a rapid reduction in the rate of coal extraction. Since 80 some percent of the world coal comes from five countries, this would not require the whole world to sign on, just the top producers (US, China, Russia, Australia, and South Africa, iirc).

    Then oil could go on a slightly slower trajectory of draw down, and NG yet slower. But the un-sequestering of all these sources has to be seen now as what it is–a crime against humanity and against life.

    Of course, this leads to the old question–who will bell the cat? (And how?)

  5. 205
    Lawrence Coleman says:

    Just been looking at the jim petitt graph for ice volume ‘death spiral’, and that would strongly indicate that an ice free summer arctic will happen sometime this decade and yet the projections for ice area and extent indicate a time around 2025+. Now surely the ice volume graph is the one we should be concentrating on as nil volume= nil area/extent. Could someone please clear up that glich in my understanding.
    Thinking post arctic summer ice here… how will an ice free arctic even for 1-2 months of the summer affect the melt pattern for the rest of the year? In my understanding it will greatly change the pattern as I’m expecting that nowhere near as much ice will be formed for the remaining months and the ice quality will be very poor. As the arctic ocean quickly begins to warm under a ‘calm air’ scenraio that probably would not be as bad since the hightened hydrologic cycle should cause appreciably more snow to fall thus trying to regain eqilibrium. What I don’t believe anyone really has come to grips with yet is how will increased ocean evaporation at the arctic latittudes affect the air currents and air masses? What I do have a strong hunch is when we do reach ice free conditions for even part of the year-all hell will break loose astonishingly quickly.

  6. 206
    Superman1 says:

    Lawrence Coleman #205,

    ” What I do have a strong hunch is when we do reach ice free conditions for even part of the year-all hell will break loose astonishingly quickly.”

    I have addressed this issue in previous posts. Briefly, I believe all Hell broke loose when substantial open water appeared in the Arctic sea. Many new phenomena appeared that contributed to positive feedback, all synergistically reinforcing each other. Forgetting about the models with their myriad limitations, when one visualizes the physics of what is happening, it is crystal clear that Nature is pulling out all the stops to eliminate the ice.

    We humans like to think of slow agonizing declines. We keep people on life support who have no chance of regaining any effective consciousness, and we prolong other endeavors. That’s not how Nature tends to operate. When the day arrives that the slowest gazelle in the pack cannot outrun the fastest lion in the pride, he’s finished, and the end is usually brutal and swift. I believe the physics of what is happening to the Arctic sea ice is a template for the other effects of global warming. I don’t believe these ‘evolutionary’ predictions that are reported in the Press, or in much of the technical literature. They are not based on models that contain all the known phenomena that contribute to positive feedback loops, and they especially don’t show the effects of the synergies of these positive feedback phenomena. My reading of the physics is that the aged gazelle is a much better model of what we have in store for us.

    “Now surely the ice volume graph is the one we should be concentrating on as nil volume= nil area/extent.”

    The global situation appears monolithic with respect to climate change, and any metrics selected to describe this situation should have similar profiles. Sea ice area/extent are not the best choice because of their inconsistency.

    I used to do computational fluid dynamics. Initially, researchers would solve the flowfield problems using variables such as pressure, temperature, velocity, etc. Their values could vary tremendously within the flowfield, especially near and across discontinuities, and this would wreak havoc with the stability of the numerical solutions. When the community switched to conservation variables, such as mass, momentum, and energy, the numerical oscillations decreased substantially, because these variables were essentially unaffected by discontinuities et al.

    That’s what we need to describe the evolution of climate change. Hansen had a good idea in his recent paper using numbers of extreme events. They tend to trend monolithically, and if one type of extreme is down this year, another type will be up, and the overall sum will increase. So, we need integral-type metrics or maybe even ‘signatures’ of metric combinations that are not dependent on any one of the components to convey the message. The ‘deniers’ will focus on non-monolithicity of the components, but presenting integral monolithic metrics will make their job much more difficult, and will convey the true nature of what is happening to the public, and the research community as well.

  7. 207
    SecularAnimist says:

    Superman1 wrote: “We humans like to think of slow agonizing declines.”

    Actually, I find that I don’t really much like to think of slow agonizing declines. But that’s just me.

  8. 208
    Ron R. says:

    Rob Dekker @ 3:44 AM: Instead, drafting geo-engineering plans gives us a sense of the cost of what it takes to clean up after ourselves.

    Aye. Good point. Maybe if we put a monetary and environmental price tag on after the fact clean up the powers that be will take notice. I heard a saying once, There’s never time to do things right the first time, but there’s always time to do it over. If we know something is inevitable, something that we have to do and should do now, it’s better to just do it and get it over with than keep putting it off (to a time when conditions may have deteriorated and waste all that time). To borrow a phrase, Just do it.

    The same massive level of technology innovation and financial investment needed for the sunshade could, if also applied to renewable energy, surely yield better and permanent solutions. A number of technologies hold great promise, given appropriate investment.

    Right. But it’s discouraging, the blatant corruption by those in power to preserve the status quo. Sometimes I fell like we’re still living in ancient Rome, or that we as a species have a death wish, what with all of our many assaults on the environment.

    Anyway, it’s good to divert our energies toward solutions rather than just griping about how bad things are. Thanks.

  9. 209
    Superman1 says:

    SecularAnimist #207,

    “Actually, I find that I don’t really much like to think of slow agonizing declines. But that’s just me.”

    Wrong choice of words. Should have used ‘tend’ rather than ‘like’.

  10. 210
    Ron R. says:

    Superman1 wrote: “We humans like to think of slow agonizing declines.”

    SecularAnimist: Actually, I find that I don’t really much like to think of slow agonizing declines. But that’s just me.

    I understand what he means. Look at all the disaster movies out. It’s been non-stop since The Towering Inferno. Problem is, while it may be fun to watch cataclysms when they happen on the big screen to other people, disasters are never fun and are always a lot worse when they happen to you in real life.

  11. 211
    Steve Fish says:

    Re- Comment by Jim Larsen — 13 Sep 2012 @ 10:50 PM currently #195:

    An all-electric vehicle gets 99mpg (gallon of what?) which you have to divide by three? Please document this strange formula.

    You “assume that our mix of coal, n-word, CH4, and renewables is about as carbon intensive as oil.” No assuming. How much CO2 for each? How much per mile in an electric vehicle?

    You have made a bunch of unsupported assumptions about the cost of producing a barrel of oil (no actual numbers) and eliminated a large chunk (no numbers) in support of your previous $2-$25/barrel oil. Document this.


  12. 212
    Jim Larsen says:

    Patrick, the supply/demand curves for fossil fuel are not “in the present”. Producers decide whether to increase capacity based on projected price perhaps 5 years in the future. Yes, they can make minor changes in existing production, but such decisions have future ramifications. I read an article about how Iraq had messed up their fields by producing too fast. Basically, production is a slow decline, bumped up periodically by a decision to develop a new field.

    Consumers make some decisions immediately. Increase the price, and they drive a bit less or heat/cool the house a degree less. But mostly, they are stuck with the house, the commute and the car they own. And even if they sell the house and car, somebody else will own them, thus reducing consumption not a jot until the house and car become landfill (or the house is upgraded). Want to help the planet? Don’t sell the SUV and buy a Prius, burn the SUV and take the loss.

    So, increase or decrease the price, and you hear cries of anguish and joy, but production and consumption don’t change much. Here’s an estimate of costs for fossil fuels.

    Note that lifting costs are from $6 to $13 a barrel. (I’ve read lower figures, down to $2 a barrel for Saudi, but let’s stick with these figures) Thus, the owners of all existing fields will pump as long as oil remains above $13 a barrel. I think it is safe to assume that price point is a given.

    Look at US offshore figures. $52 a barrel total. Producers will drill if they believe the minimum price ~5 years in the future will be well above $52. Say they’re wrong, and oil is $40 a barrel in 2017. What does the producer do? Well, lifting costs are $10, so they pump like mad, losing $12 a barrel. Since they’re recovering losses, the incentive to pump might even increase – panic does that sort of thing.

    Oil prices are kinda like the game of Chicken. Consumers and suppliers buy infrastructure that locks each into a set pattern. After that, neither has any bargaining power at all, other than faking it. Thus, traditional supply and demand curves are inappropriate.

  13. 213
    Hank Roberts says:

    American Medical Association 2012
    CSAPH Report 4-A-12
    … an emerging consensus has come to acknowledge the effects of widespread nighttime artificial lighting, including the:
    1) impact of artificial lighting on human health, primarily through disruption of circadian biological rhythms or sleep;
    2) intersection of ocular physiology, vehicle headlamps, nighttime lighting schemes, and harmful glare;
    3) energy cost of wasted and unnecessary electric light; and
    4) impact of novel light at night on wildlife and vegetation….
    … this report evaluates the effects of pervasive nighttime lighting on human health and performance. Concerns related to energy cost, effects on wildlife and vegetation, and esthetics are also briefly noted.

  14. 214
    Jim Larsen says:

    203 Ray said, “With all due respect, you are full of beer and beans. The oil counts for a minority of the cost. Processing of the petroleum is not free. Those plants are expensive–both to build and maintain. Look into the economics before spouting off.”

    Uh, I did. You tell me how the economics work for refineries if we drop ff production by half. Capital costs CAN’T be recovered except by production. Or explain how a refinery can be unbuilt? Perhaps you need to take your own advice?

    Here you go: 30-60 CENTS a gallon. Gee, at $3.75 a gallon, that 50 cents surely is the deciding factor, right?

  15. 215
    Jim Larsen says:

    OK, to make it clear, markets are either increasing or decreasing. In an increasing market, capital costs are way important. You build a refinery or drill a well because it will be profitable.

    Conversely, in a decreasing market, capital costs are sunk. Therefore, they can be set to $0 and only operating costs matter. Old versions of Windows still sell at what might be considered a net loss, but at a fantastic profit in reality as the capital cost has been set to $0.

    Given that we live on Earth, and Earth requires that we enter a declining market for fossil fuels for which all required capital costs have already been paid, capital costs are irrelevant to business decisions, other than the decision to commit planetary suicide.

    So, Ray, you can join the climate change deniers, or you can accept reality. Economics either follows physics or it leads to death and destruction.

  16. 216
    Jim Larsen says:

    And $100/barrel divided by 42 = $2.38 a gallon, which is a MAJORITY of $3.75 a gallon. (fiddle the numbers as desired, but the point is solid.)

    Seriously, dude, when you read a comment that feels wrong, you ought to do some research before shouting beer and beans…

  17. 217
    Hank Roberts says:
    ” one of the most interesting documents Freedom of Information (FOI) discosures from the UK Department of Energy and Climate Change (DECC) has uncovered is the all-caps transcript of a speech on climate communications delivered by one of the department’s officials. The presentation, which Guardian journalist Leo Hickman publicised along with other documents, reflects on the handling of the Climategate email hack, advocating better engagement with the public on tangible aspects of climate science.”
    Climategate, caps-lock, skeptic rebuttals and industry chats: DECC’s FOI treasure trove

  18. 218
    Dan H. says:

    Well pur Jim

  19. 219
    dbostrom says:

    Solar shades sound wonderful until we get close enough to see details emerge. Kind of like simple, fuzzy canals on Mars turning to a myriad of little fragments of rock, dust once we’d zoomed in on the planet enough to gain some acuity.

    The shades remind me of space power systems. Shiny, but the numbers are cruel. Let alone launch costs, etc. what happens when the inefficiency of transmission systems needs to be disposed of? 90% efficient leaves a big problem called incandescence if it’s ignored. That’s another interesting exploration.

    Boondoggle about sums it up, though the costs of funding studies are probably worth it for accidental collisions with useful information.

  20. 220
    jjm says:

    Are there any reputable scientists out there that see a suspicious negative forcing component in their recent observations? I am trying to find a long-lived SOx indirect effect or (am concerned) that I am finding evidence of climate remediation. help???

    not allowing a second post of the first due to incorrect captcha

  21. 221
    Steve Fish says:

    Re- Comment by Jim Larsen — 14 Sep 2012 @ 12:01 PM, currently #212:

    OK, so we now have the Lifting Cost per barrel ( ) that is greater than your $2/ barrel figure. Now add in the cost of development and drilling, refining, transportation before and after refining, marketing, and the actual number of gallons of gasoline that resulted. This is like extracting teeth and, therefore, supports the beer and beans hypothesis. With a little more evidence the hypothesis will become a theory. Steve

  22. 222
    Patrick 027 says:

    Re 211 Steve Fish – That reasoning is based on the understanding that the 99 mpg figure comes from equating a kWh of electricity with a kWh of the heat (enthalpy, presumably) of oxidizing gasoline.

    Given the prevalence of fuels in our present energy supply, it is understandable to want to convert electricity to fuel equivalent for comparison purposes or to be able to express the whole in terms of one type of energy – the EIA does this, for example (unfortunately in different units. It would be nice if they had the option to see all tables in GW). But they have the good sense to take into account the efficiency of conversion of fuel to electricity (the place this gets tricky is in CHP power plants, but those are a small fraction of the total – try looking around here ). If a large amount of primary energy were nonfuel (or non-fuel to us – the sun is fusion power of course but we aren’t the ones making that happen so…), and most easily accounted for as electrical energy, and if we wanted more fuel (for combusting) than could be readily obtained in other ways, then fuel might instead be produced from electricity and fuel would be given in electrical equivalent with a very different conversion factor. (Of course fuel->electricity and the reverse could happen in the same overall supply system, because of temporal and spatial variations).

    Anyway, it would be ideal to give the mpg value in terms of the amount of gasoline that would have to be burned in a power plant to produce the necessary electricity, including transmission+distribution losses. But we don’t tend to use gasoline that way, other fuels have different EROEIs and LC’s, etc.

    If the economic savings from converting to (PH)EVs were diverted to (or used to smooth the way for) clean energy investments, though, then the bigger picture would look better for them.

  23. 223
    Patrick 027 says:

    re solar shade – my point about UV was that, as far as I understand it, if we reduced the wrong part of the UV spectrum (shorter than ~200 nm), we could end up increasing the amount of UV that reaches the surface.

    About launching things into space – might it be easier to steer a small asteroid into the L1 position and periodically set off explosions to produce dust clouds (or maybe that would actually be much harder)? Of course, if the forward scattering dominates and/or the cloud’s area is too large, we could have the reverse of the intended effect. (Actually, explosions would needlessly scatter the dust. Just have a robot with a shovel…)

  24. 224
    Steve Fish says:

    Re- Comment by Patrick 027 — 14 Sep 2012 @ 5:03 PM currently at 221:

    I thought that the 99mpg figure consists of something like you say, but Jim Larsen should document it and explain why it then must be divided by three to substantiate his claim that electric vehicles are more carbon intensive than hybrids and ICE (internal combustion engine) vehicles. I suspect that power plant efficiency is not very different than an ICE engine and that power line transmission losses are not much greater than gasoline truck transport of gasoline, so one third seems out of line. What would be most useful to know is the actual pollution/mile in an electric car for each of the different electricity generating technologies. Larsen should stop making claims and refusing to document them. If what he says is true, I would like to know why and how. If he doesn’t know he shouldn’t post.

    People who can’t back up their claims are not trustworthy. Steve

  25. 225
    Hank Roberts says:

    > suspicious negative forcing component

    How would you identify something like that?
    This is a few years old (2010); since then?
    “… earthshine data shows increasing albedo from 1999 to 2003 but little to no trend from 2003. Satellites show little to no trend since 2000. The radiative forcing from albedo changes in recent years appears to be minimal.”

  26. 226
    Patrick 027 says:

    Re Steve Fish – I think some of us may have gotten into this and some other recent topics sometime over a year ago. I’ll have to look back through earlier unforced variations (unless someone else remembers just where exactly those comments were – anyone?). Just off the top of my head, some improvement in efficiency just from going from ‘conventional’ to HEV comes from regenerative breaking, lack of idling, and maybe increased transmission efficiency (?). I vaguely recall 40 % efficiency being stated for *some* IC engines…

  27. 227
    Jim Larsen says:

    221 Steve F wondered about lifting costs.

    Yes, I decided to accept $6 because it was easy and didn’t matter, but slap me with it and I’ll go for the facts:

    “It is costing Saudi Arabia dear to burn through so much oil. With “lifting” costs of $3 to $5 a barrel the fuel is cheap”

    So $3/barrel is the lowest, according to The Economist. (I’m reading it as some wells in Saudi are $3, and some are $5) Thus, my perhaps decade old remembered reference was pretty durn accurate, eh? A bit of inflation, a bit of difference of opinion, a bit of aging in Saudi’s wells, and it’s a bulls-eye when the reference is $100/barrel. (and IIRC I qualified $2 with “perhaps” or about”. If not, I pseudo-apologise) Market fluctuations during transit is as/more important to Saudi and their customers as/than lifting cost. Quibbling about gnats, you are.

    And you’re trying to backdoor sunk costs! Those supertankers exist. Ditto wells, pipelines, refineries, even gas stations. This is NOT about oil/CH4 VS refinery/pipeline/tanker. It’s about sunk capital cost VS operating cost throughout the supply chain. Construction is based on profit. Retirement is based on operating cost. Never the twain shall meet. Let’s look at refineries:

    “The refinery complex will cost about $10 billion to build,….and process up to 400,000 barrels of gasoline and diesel fuel each day.”

    At 30-60 cents/gallon gross, operating costs had better be way small for a $10 bil investment to pay off.

    And as fig 3 in the link way above shows, all fossil capital investment needed to supply the world with as much fuel as we can afford to burn has already been made. This ain’t Monopoly. You can’t sell that refinery back to the bank. Future capital investment in fossil fuels is not just a waste of money, but a recipe for planetary disaster as turning off a massively capital intensive operation is almost impossible.

    Seriously, look at fig 3 again. It is the KEY to my entire argument. Compare it to what the scientists here are telling us we NEED to do and tell me if you believe the drilling of a single additional well is smart. Yeah, we can whine, but Saudi got to their oil first (not literally true, but you get the drift), and they ain’t gonna stop pumping just because we want our turn. Maybe we can drill our wells and then bomb Saudi….

    Got any other teeth to pull? :-)

    By the way, though a barrel is 42 gallons, you get ~44.2 gallons of product. Values vary, but again, it’s quibbling.

  28. 228
    Jim Larsen says:

    224 Steve F said, “. Larsen should stop making claims and refusing to document them.”

    Hey, dude, I’ve documented every single thing I’ve been challenged on. Yeah, I make statements based on blatantly obvious common knowledge (or so I thought) and don’t cite them until somebody demands I explain the obvious. Since you’re now challenging my divide by three rule of thumb, I’ll, as always, document:

    “ratings are based on EPA’s formula, in which 33.7 kilowatt hours of electricity is equivalent to one gallon of gasoline,”

    “Gasoline (base)[2] 1.0000 100.00% 114,000 33.41″ <–33.41 KWH

    So, 33.41 or 33.7, eh, rounding error. So MPGe is based on 100% efficiency for power plants and transmission.

    "To express the efficiency of a generator or power plant as a percentage, divide the equivalent Btu content of a kWh of electricity (which is 3,412 Btu) by the heat rate. For example, if the heat rate is 10,140 Btu, the efficiency is 34%; if the heat rate is 7,500 Btu, the efficiency is 45%."

    Click on the historical link and you'll find that in 2010 efficiency was from 8,185 for CH4 to 10,415 for coal and 10,984 for oil. So, perhaps 36%.

    "Transmitting electricity at high voltage reduces the fraction of energy lost to resistance, which averages around 7%."

    0.36 * 0.93 = 33.5%. QED :-)

    Now it's your turn, Steve. Document a SINGLE instance where I refused to provide a cite OR my cite OR ANYBODY ELSE'S CITE invalidated ANY point I have made during this discussion. Seriously, this is a recurring theme. I make an obvious statement, some folks think it's outrageous, and I wander off to the web to provide a random cite. After 20 or 30 times I'd expect folks to actually take 30 seconds to check before spouting, but nope, they always stick their foot in their mouth….

  29. 229
    Jim Larsen says:

    204 wili said, “Of course, this leads to the old question–who will bell the cat? ”

    EXACTLY! We want us to make $48/barrel while refusing Saudi’s $97/barrel. As if, eh?

    You boiled down my argument to perfection!

  30. 230
    Marcus says:

    Completely off topic and personal question to Ray Ladbury:
    Did You, once upon a time, use to post in the forum of the project, or do I confuse You with
    someone else here.


  31. 231
    dhogaza says:

    So, 33.41 or 33.7, eh, rounding error. So MPGe is based on 100% efficiency for power plants and transmission.

    And your comparison assumes 100% efficiency for the movement of gasoline from the ground, through the refinery, and to the local pump used to fill the car.

    You’re oversimplifying in order to get the result you want.

  32. 232
    dhogaza says:

    My guess is that the EPA has thought of such things, and lo and behold, it appears they do.

    They make available a CO2 emissions calculator here:

    In my region (heavy on hydro) total end-to-end CO2 emissions are estimated at 150g/mile for a Nissan Leaf, compared to 500g/mile for the average gasoline car.

  33. 233
    MARodger says:

    Re the carbon intensity of US electricity.
    The US EPA MPGe works out at 89gC/kWh. On what they base this, I know not. I have come across a figure for primary energy carbon intensity for the US electric grid at 18gC/MJ = 65 gC/kWh. The UK electric grid carbon intensity for power deliverd is about 130g/kWh. The US figure (which I have seen but cannot remember) is higher but not by much. Perhaps 150 gC/kWh would be about right.
    It does imply that to compare petrol & electric cars, MPGe should be multiplied by a figure a little less than 2.

  34. 234
    Jim Larsen says:


    Excellent point about MPG (which Steve F also alluded to). I should have taken the time to do a similar bit with MPG as I did with MPGe. This site says it’s about 19% losses. (though I just glanced, and the site doesn’t feel robust) So, a second rule of thumb is you have to multiply MPG by 4/5ths to get to reality. So, the Prius T3, which gets 60.3MPG really gets about 48MPG, and the regular Prius’s 50MPG becomes 40MPG. Compare to the Leaf’s 33MPGe, and either Prius still wins.

    Nifty calculator. Thanks! But there’s a couple inaccuracies. The odds that a Leaf purchaser would buy a SUV instead are about 0%, so “average car” isn’t the proper comparison. I’ll go out on an unsubstantiated limb and say 99.9% of Leaf purchasers would have bought the Pruis or something with similar efficiency instead. Plus, energy spent in manufacture is different. All those batteries take KWH to build. Also, the actual CO2 contribution of an electrical load is determined by what was added to the grid to provide that power. N-word and renewables are generally the first to go on line, as they have low/no fuel costs. So the last-KWH-produced is probably going to be fossil. I’ll stop quibbling now and just go with your calculator:

    The calculator didn’t have the regular Prius, but it has the plug-in version and assumed 28% electrical propulsion. Using US average, the Leaf spews 230 grams/mile and the Prius spews 210. So, your cite says the Leaf makes global warming worse. Thanks for confirming my claim.

    Now, in France the Leaf is golden!

  35. 235
    Ray Ladbury says:

    Hi Marcus,
    No. I’ve never posted at Looks interesting, though.

  36. 236
    dbostrom says:

    Seems we’ve found a replacement for the “argument that will never be agreed.”

    Decay, so to speak.

  37. 237
    dhogaza says:

    I’ll go out on an unsubstantiated limb and say 99.9% of Leaf purchasers would have bought the Pruis or something with similar efficiency instead.

    Nice goalpost move from “electric vs. gasoline powered car” to “electric vs. gasoline hybrid car” … also I didn’t see the bit on the calculator page that states that their “average car” is an SUV.

    Jim’s earlier statement:

    current electric cars produce more CO2 than fossil fuel cars, and that will remain the case for as long as current cars are still on the road, so every electric vehicle sold today makes global warming worse

    EPA calcuator suggests 500g/mile for your average fossil fuel car, 230g/mile for the Leaf.

    Post-goalpost move:

    The calculator didn’t have the regular Prius, but it has the plug-in version and assumed 28% electrical propulsion. Using US average, the Leaf spews 230 grams/mile and the Prius spews 210. So, your cite says the Leaf makes global warming worse.

    Worse than the Prius PHEV, not the average gasoline car.

    Your first claim was that electric cars like the leaf emit THREE TIMES AS MUCH carbon as existing gasoline cars. Even if we allow your goalpost move (I’m not, perhaps the more generously-minded among the readers will) 230g/mi is not 3x the 210g/mi stated for the Prius PHEV (which is also partially an electric vehicle, so by your rationale ought to be worse than the standard Prius).

    You’re just playing games.

  38. 238
    dhogaza says:

    And, Jim, no one here is going to argue against the need to continue to support renewables such as wind and solar power, reduction of coal-fired power plants, etc. This is needed regardless of the number of EVs on the road. Each coal-fired watt that’s replaced by a renewable makes the EV look better …

  39. 239
    Steve Fish says:

    Re- Comment by Jim Larsen — 14 Sep 2012 @ 11:07 PM and subsequent:

    First, my name is Steve Fish. Steve F is another guy who posts here sometimes and this kind of confusion has been annoying for some people on this forum in the past (e.g. Septic Mathew). You’re Jim Larsen. I’m Steve Fish. So that’s what you call me. That, or His Fishness, Stevo, or El Steverino if, you know, you’re not into the whole brevity thing.

    Second, you now admit that your multiple recent posts were wrong and you didn’t provide accurate and appropriate documentation. Dhogazqa has pretty much nailed down your claims regarding electric vehicles and in my area the Leaf emits only 24% as much CO2 as the average new vehicle and is better than the Prius (in CA the Leaf is golden). Even in Missouri, the state most dependent on coal for electricity per person ( ) the electrics are much better.

    Also, lifting cost as per US Legal Definitions that I linked above “consists of those deductible costs incurred in the production of oil and gas after completion of drilling and before its removal from the property for sale or transportation.” The expense of just pumping crude is a small component of the actual cost of a barrel of oil.

    As this is an educational site, it is only polite to provide accurate information and relevant sources so others can learn and follow a discussion. This is also how scientists communicate accurately.

    I agree with Dhogaza’s disclaimer at ~238. Steve

  40. 240
    Jim Larsen says:

    Digging into the calculator’s details page, “On average, 8,887 grams of CO2 are emitted from burning one gallon of gasoline”

    8,887/40 = 222 grams/mile for the regular Prius. Close race, but it still beats the Leaf’s 230, so I can still do the happy dance. But the Leaf will drop its emissions a bit over its lifetime, so perhaps it’s a statistical tie. Add in the last-KWH and manufacturing stuff, and I’m convinced my original claim was correct, but I’ll modify it slightly to “Assuming the alternative is a 50MPG car, mid-size electric cars sold in the USA today will not help with AGW”

    Interestingly, the details page contradicts the calculator. It says plug-in hybrids are assumed to be 64% electric while the calculator says the Prius was rated using 28.8%.

    I wasn’t convinced Wiki was right about the Prius T3, and yep, other sources say it’s bunk.

    And on the horizon is VW’s 282MPG XL1.

  41. 241
    numerobis says:

    @Jim Larsen:

    Actually, coal plants are among the first you turn on, because you don’t want to toggle them on/off. Toggling wind and hydro plant is almost free. Hydro makes a good battery even: restrict streamflow at night and the water piles up ready to gush through during peak times.

    If you’re building new plants, you’re going to build whatever is cheapest, including political considerations. Right now in much of the West that’s coal, gas, and wind. In places with carbon taxes, coal gets a lot more expensive. In Quebec, hydro is king because there are major rivers with politically powerless people living on their banks.

  42. 242
    Hank Roberts says:


    “…. large changes in the precipitation extremes: about 100% increase for the annual top 10% heavy precipitation and about 20% decrease for the light and moderate precipitation for one degree warming in the global temperature. These changes can substantially increase the risk of floods as well as droughts, thus severely affecting the global ecosystems.”

    How much do precipitation extremes change in a warming climate?

  43. 243
    Hank Roberts says:

    “The best thing you can do with science today is use it to explore the present. Earth is the alien planet now.”
    —William Gibson in an interview on CNN, August 26, 1997.
    (from Wikipedia)

  44. 244
    Superman1 says:

    Hank Roberts #242,

    Equally important is their perceived reason for the climate models not predicting this increase in extremes accurately:

    “In comparison, coupled climate models are capable of simulating the shape of the change in precipitation intensity, but underestimate the magnitude of the change by about one order of magnitude. The most likely reason of the underestimation is that the typical spatial resolution of climate models is too coarse to resolve atmospheric convection.”

    This leads to the question: what else are the models underestimating by an order of magnitude, or more? And, given the ‘climate commitment’, or the temperature time lags of the CO2 forcing, the temperatures that are eliminating the polar ice cap and causing these massive increases in the extremes are from the CO2 we placed in the atmosphere ending decades ago. I would like to see an accurate estimation of the effects resulting from the CO2 we have placed in the atmosphere to date.

  45. 245
    dhogaza says:

    Jim Larsen:

    8,887/40 = 222 grams/mile for the regular Prius. Close race, but it still beats the Leaf’s 230

    I see we’re back to ignoring the CO2 emissions involved with drilling, transporting crude, refining, and transporting gasoline to the local pump. Tch tch, Jim.

    I’ll modify it slightly to “Assuming the alternative is a 50MPG car, mid-size electric cars sold in the USA today will not help with AGW

    That’s a substantial walk-back from your original position … it is equivalent to saying that electric cars are substantially better than the average gasoline car in the city, the opposite of your original claim.

    And, as I pointed out long ago, in my region it’s 150gr/mi, while emissions for the hybrid will remain the same. That’s a 1/3 advantage for the electric car in my region.

    You are only able to turn “better” into “not better” by moving the goalpost from gasoline cars to hybrids. The hybrid vs. electric argument’s not particularly controversial, which is one reason why hybrids are popular and is why the EPA calculator site is there – it’s to help you decide which is more CO2-friendly in your region given the sources of electricity available to you. They don’t bother with traditional gasoline vehicles because they suck in terms of CO2 emissions vs. both hybrids and ev.

    People might pay more attention to you if you were to say something like “OK, I was wrong to claim that pure gasoline cars emit less CO2 than gasoline cars when considering the entire energy delivery system, but hybrids are just about as good as electrics”. Instead, you’ve moved the goalposts a couple of times and declared victory.

    EVs also have the substantial benefit of not contributing to local smog and the ensuing health problems that come with smog.

  46. 246
    dhogaza says:

    And on the horizon is VW’s 282MPG XL1.

    Thought to come in at more like 150 mpg using US mileage calculations.

    How does it do it? By being a PHEV with a 21 mile EV range. So all of your arguments about EVs will weigh equally against the VW XL1 to the extent that the latter’s driven as an EV.

  47. 247
    Superman1 says:

    Jim Larsen et al,

    The debate on electric vs gas vehicles, and among the different electric vehicles, is interesting, but it suggests the following. A three-pack a day smoker goes for his annual physical checkup. The Dr. tells him he has Stage 4 lung cancer. The smoker goes home, and argues with his wife whether he should cut back to two packs a day or 2 1/2 packs.

    That’s where we are today. As I have posted previously, if we were to eliminate fossil fuel combustion tomorrow, we will have generated a temperature increase over pre-industrial of from 2.5 to 3.0 C. Of this total, we have a temperature increase today of 0.8 C, we have a ‘climate commitment’ of about 0.7 C due to the temperature lag from the CO2 forcing, and we will have a temperature increase of about 1.0-1.5 C from the disappearance of the fossil sulphates that have been masking the true CO2 temperature increase with their increased albedo. A total temperature increase of this magnitude, which does not include the major positive feedbacks we are seeing already, will probably not stabilize at 2.5-3.0 C, and will exhibit some type of runaway. This is Stage 4 cancer applied to climate!

    So, our chain smoker above, if he wants to survive, needs not only to give up smoking completely, but needs to explore the Hail Mary pass of radical therapy, perhaps something like Gerson Therapy to eradicate the damage from the cancer. And, if we want to survive the climate catastrophe, that’s our choice. It is pointless to debate the benefits/disadvantages of the auto equivalent of Marlboros vs Camels. How do we eliminate fossil fuels completely ASAP, and how do we increase the albedo/remove CO2 from the atmosphere ASAP? We’re almost out of time.

    P.S. A NYT article ( described a comparison of electric and gas vehicles, where the conclusion was:

    “In a worst-case situation, with electric power generated from a high proportion of coal — as it is in a wide swath of the country’s midsection — an electric car or a plug-in hybrid will generate slightly more full-cycle global-warming emissions, as the report calls the greenhouse gases, than the best gasoline-engine subcompact. In areas where the cleanest electricity is available — regions served by hydroelectric, natural gas or nuclear generating plants — greenhouse gas emissions may be less than half that of today’s best gasoline-engine vehicles.” Intuitively, that’s what one would expect.

  48. 248
    David B. Benson says:

    Those interested in theoretical climatology may wish to read

    Dmitry Dolgopyat
    Repulsion from Resonances
    Memoires de la Societe Mathematique de France 128
    (Available from the American Mathematics Society in Canadan, Mexico & US)

    From the blurb:
    The author considers slow-fast systems with periodic fast motion and integrable slow motion in the presence of both weak and strong resonances. … The Markov process consists of the motion along the trajectories of a vector field with occasional jumps. …

  49. 249
    Patrick 027 says:

    From ,

    the effective efficiency of the car (a ‘conventional car’, it appears) is 9 %. This counts the energy used to overcome aerodynamic drag and rolling resistance as well as accessories.

    The efficiencies of the engine itself and the driveline itself are about 37.6 % and 69.2 %, respectively, with a product of 26.0 %. This would be the efficiency without idling or braking, but assumes no use of accessories.

    Keeping the energy usage for accessories in constant proportion to that used for aerodynamic drag + rolling resistance (the ratio is 2.2/6.8 ~= 0.3235):

    (PS I don’t know how realistic these numbers are. I increased engine efficiency by 20 %, which seems quite reasonable considering the statement that some engines (diesels) are 30 to 35 % more efficient)

    reducing breaking losses (relative to energy delivered by the driveline) by 90 % (regenerative breaking round-trip efficiency), and raising driveline efficiency to the same value (the idea being that this is round trip efficiency of mechanical->electrical->mechanical energy in each case),

    reducing idling losses (relative to what is delivered to the driveline) by 90 %,

    and using engine efficiency of ~ 45.12 %,

    The overall efficiency is now 37.0 %, 4.11 times better, requiring only 24.3 % of the original energy input. (With no engine improvement, it’s 30.8 % efficiency, 3.43 times better, 29.2 % of original energy input.)

    But if there were no idling or braking in the first place:
    Using the original engine and driveline: 28.1 % efficiency
    Improvements: 41.6 % efficiency, 1.48 times better, requiring 67.6 % of the original energy input. (With no engine improvement, it’s 34.7 % efficiency, 1.23 times better, 81.1 % of original energy input.)

    There is a link in that first link to what is identified as the source – I haven’t checked those numbers.


  50. 250
    Patrick 027 says:

    … The ‘not being sure if numbers were realistic’ applies to all the improvements I tried out. So it’s a sample calculation, which may turn out to be useful.

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