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Groundhog day

Filed under: — gavin @ 7 June 2009

Alert readers will have noticed the fewer-than-normal postings over the last couple of weeks. This is related mostly to pressures associated with real work (remember that we do have day jobs). In my case, it is because of the preparations for the next IPCC assessment and the need for our group to have a functioning and reasonably realistic climate model with which to start the new round of simulations. These all need to be up and running very quickly if we are going to make the early 2010 deadlines.

But, to be frank, there has been another reason. When we started this blog, there was a lot of ground to cover – how climate models worked, the difference between short term noise and long term signal, how the carbon cycle worked, connections between climate change and air quality, aerosol effects, the relevance of paleo-climate, the nature of rapid climate change etc. These things were/are fun to talk about and it was/is easy for us to share our enthusiasm for the science and, more importantly, the scientific process.

However, recently there has been more of a sense that the issues being discussed (in the media or online) have a bit of a groundhog day quality to them. The same nonsense, the same logical fallacies, the same confusions – all seem to be endlessly repeated. The same strawmen are being constructed and demolished as if they were part of a make-work scheme for the building industry attached to the stimulus proposal. Indeed, the enthusiastic recycling of talking points long thought to have been dead and buried has been given a huge boost by the publication of a new book by Ian Plimer who seems to have been collecting them for years. Given the number of simply made-up ‘facts’ in that tome, one soon realises that the concept of an objective reality against which one should measure claims and judge arguments is not something that is universally shared. This is troubling – and although there is certainly a role for some to point out the incoherence of such arguments (which in that case Tim Lambert and Ian Enting are doing very well), it isn’t something that requires much in the way of physical understanding or scientific background. (As an aside this is a good video description of the now-classic Dunning and Kruger papers on how the people who are most wrong are the least able to perceive it).

The Onion had a great piece last week that encapsulates the trajectory of these discussions very well. This will of course be familiar to anyone who has followed a comment thread too far into the weeds, and is one of the main reasons why people with actual, constructive things to add to a discourse get discouraged from wading into wikipedia, blogs or the media. One has to hope that there is the possibility of progress before one engages.

However there is still cause to engage – not out of the hope that the people who make idiotic statements can be educated – but because bystanders deserve to know where better information can be found. Still, it can sometimes be hard to find the enthusiasm. A case in point is a 100+ comment thread criticising my recent book in which it was clear that not a single critic had read a word of it (you can find the thread easily enough if you need to – it’s too stupid to link to). Not only had no-one read it, none of the commenters even seemed to think they needed to – most found it easier to imagine what was contained within and criticise that instead. It is vaguely amusing in a somewhat uncomfortable way.

Communicating with people who won’t open the book, read the blog post or watch the program because they already ‘know’ what must be in it, is tough and probably not worth one’s time. But communication in general is worthwhile and finding ways to get even a few people to turn the page and allow themselves to be engaged by what is actually a fantastic human and scientific story, is something worth a lot of our time.

Along those lines, Randy Olson (a scientist-turned-filmmaker-and-author) has a new book coming out called “Don’t Be Such a Scientist: Talking Substance in an Age of Style” which could potentially be a useful addition to that discussion. There is a nice post over at Chris Mooney’s blog here, though read Bob Grumbine’s comments as well. (For those of you unfamiliar the Bob’s name, he was one of the stalwarts of the Usenet sci.environment discussions back in the ‘old’ days, along with Michael Tobis, Eli Rabett and our own William Connolley. He too has his own blog now).

All of this is really just an introduction to these questions: What is it that you feel needs more explaining? What interesting bits of the science would you like to know more about? Is there really anything new under the contrarian sun that needs addressing? Let us know in the comments and we’ll take a look. Thanks.


1,071 Responses to “Groundhog day”

  1. 951

    Max writes:

    wind would only cover a very small part of the growth

    So explain the fact that 42% of the new generating capacity installed across the USA last year was wind.

  2. 952

    BobFJ,I didn’t look at the “easier” graphic and so don’t have a comment on it.

    I think there’s good value in looking at the Trenberth chart we’ve been discussing. Yes, I did notice that your numbers summed to 100%. It may seem counterintuitive, but they shouldn’t.

    An analogy: Three college roommates sublet their apartment at cost–$1000 per month. Upon receiving their first check from their renter, Al cashes it and distributes the funds. He pays Bob $100 for concert tickets to a show they plan to attend, Bob pays Charley $100 owed on a bet, and Charley gives Al $100 as a down payment on his motorcycle. They then pony up the $1000 for their landlord.

    So, $1000 in, $1000 out for the total budget. Each student has $100 + $333.33 in and out. Everything balances. Yet total transactions ($1300) exceed the total cash involved in the flow ($1000.) A similar situation exists with the graphic (and the real system!) as there are flows and reflows among system components. If you want to account for these, you are forced to “double count” some energy.

    That’s what I was trying to point up by giving the totals for surface budget vs. the TOA budget. I copy that here to conclude:

    The surface budget balances like this:

    168 (solar ER) + 324 (atmospheric ER, AKA “back radiation”)=24 (thermals) + 78 (E-T) + 390 (surface radiation)=492.

    The TOA budget balances like this:

    342 (solar ER)=235 (LW ER) + 107 (reflected solar)=342.

  3. 953
    manacker says:

    Patrick 027

    Thanks for your 933.

    You ask me: “Are you against an emissions tax, or an analogous cap-and-trade [scheme]”

    The answer is “Yes”. I have seen no studies that demonstrate that these schemes will have any discernable impact on our planet’s climate, whereas they will represent a major cost to every citizen of the nations participating and make a few already wealthy individuals ever richer.

    If you can demonstrate that these schemes will have a discernable impact on our planet’s climate, please do so with some specific numbers, actions financed by these taxes, specific reductions in atmospheric CO2 concentrations reached through these actions and specific degrees C of global warming averted by them.

    I have figured that the combined efforts of curtailing all new coal-fired plants in the USA starting in 2010 plus shutting down half of the existing coal-fired plants there by 2050 would cost around 1 trillion US$ over the 40-year period, reduce the projected year 2050 atmospheric CO2 content by 5 ppmv (from 462 to 457 ppmv) and avert 0.05 degrees C of global warming.

    This cost is based upon replacing the coal capacity with nuclear generation; the cost would even be higher if one tried to replace the coal plants with wind or solar (if it were even technically feasible to do). Assuming that the 1 trillion dollars are financed by a carbon tax or cap and trade (another indirect tax), it is a very poor investment of the public’s money.

    If you would like to see the backup calculations for this, let me know.

    The “guilt factor” (i.e. is it China or the USA) leaves me cold, since I believe that “guilt” should be kept out of the equation, as it brings no positive solution. One ton of CO2 has the same theoretical impact on our climate as another, no matter where it came from.

    As to providing taxpayer-funded support to some selected companies who are developing photovoltaic technology and will thus benefit from these subsidies to increase their profits, you wrote, “But even with a tax justified by perfect market principles, an initial subsidy may make sense because supply-demand curves can have kinks (mass market advantages).”

    If there were, indeed, a viable strategic reason agreed to by the voters of this world to switch a major part of the power generation system from fossil-fuel (or nuclear) powered to solar-powered technology, and if it appeared that this is an economically viable target long-term, then this could be true as a “jump start” to help these companies. So far I have seen no convincing arguments that a large part of the power demand can be economically covered by solar power (with the exception of small domestic units backed up by the power grid when there is no sun).

    Max

  4. 954
    manacker says:

    Kevin McKinney

    Sorry for cutting into your exchange with Bob_FJ (and I am NOT going to get involved in discussing the Trenberth chart with you) but your college student example caught my eye.

    It sort of reminds me of the “left pocket, right pocket” analogy. No matter how many times you switch from one pocket to the other, you are neither “creating or destroying wealth”.

    Max

  5. 955

    Re 954–You’re right, the total money (or energy) is conserved.

    But if you are talking about percentages of budget, you have to allocate correctly. In my analogy, for example, one of the $100 transactions is 10% of the lease budget, but 23% of each student’s budget, and not quite 8% of the total transactions.

    In the case of the Trenberth diagram we were discussing, the Evapo-Transpiration is not, as Bob has been thinking, 78/168 (46%), but rather 78/(168+324) (16% of radiation absorbed by the surface.) The surface “account” is–oh, hell, let’s live dangerously and call it “inflated”–because there are multiple “transactions.” The ER emitted by the surface, you will note, is 390 W/M2 (80%), but only 40 W/M2 (8%) makes it directly to space.

    And since you’re “cutting in” to my discussion with Bob, let me return the favor. In your discussion with Patrick, you ask for some specifics about cap-and-trade schemes. I’m not trying to answer all your questions/demands, but here’s an interesting paper from 2005, modelling different implementations of the Regional Greenhouse Gas Initiative. If you scan the tables, you’ll find that most approaches modelled result in US reductions of 200-300 million tons of CO2 by 2025, even though the RGGI only includes Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, and Vermont. (BTW, they decided to go with an auction approach–auction day is Sept. 9.) There is also the Western Climate Initiative, including seven states and four Canadian provinces. Their plan calls for a reduction of 15% from 2005 emissions levels by 2020.

    In each case, the reduction will be a tiny fraction of what is needed. But the whole point is for everybody to contribute a tiny fraction of what is needed. It’s not guilt, it’s responsibility–a big difference: guilt is lamenting what you should have done, responsibility is doing it.

    Study URL:
    http://ageconsearch.umn.edu/bitstream/10650/1/dp050025.pdf

  6. 956
    Mark says:

    “Re 954–You’re right, the total money (or energy) is conserved.”

    Not any more.

    Fractional reserve banking and the creation of “new wealth”, such as extended copyright, trademarks and so on all increase the money supply.

  7. 957
    Doug Bostrom says:

    #948 Manacker:

    “The point I was making is not that these systems are not efficient, just that they are unlikely to become a major factor in the overall energy picture, due to two factors: first they are limited in size to local solutions where thermal energy is required and second there is no big government subsidy in the offing for profit-hungry big businesses, as there is for photovoltaic or wind in many countries.”

    That really makes no sense.

    A kilowatt hour saved is a kilowatt hour saved, regardless of where the kilowatt hour started and where it ended up. If the total amount of kilowatt hours saved is large, then a significant change in consumption has been achieved.

    Hot water heat is roughly 20% of domestic energy consumption, here in the U.S. anyway. Eliminating half of that via capture from sunlight is a large reduction in demand in absolute terms and as a fraction of our total consumption is an extremely worthwhile incremental target.

    In many parts of the world solar water heating is bog standard and did not require any sort of government interventions or subsidies. It’s employed because it’s cheaper for consumers to heat water via solar. The real world does not agree with your aversion to free money; most people like things that are less expensive.

    As I’ve said, who cares about efficiency? Low grade thermal energy is freely available and there’s so much of it in such dense amounts that pursuing efficiency is sort of silly, especially if doing so makes the energy too expensive to capture.

    My central beef here is that we’re skipping a first step, something really easy and offering a significant improvement, in favor of something much harder to do and that will offer less benefit if we do skip the first step.

    How much sense does it make to capture energy via relatively expensive and cumbersome means thereby converting it into a form of the very highest quality, only to convert it into low quality heat? Why would we take the output of PV and wind generation systems and use it for the very crude requirement of heating water when the heat we want is much more cheaply available? Wouldn’t we want to save the high quality energy for duties such as motive power?

    Again, this has to do with residential requirements. Efficiency matters more in the case of multi-family dwellings, some industrial settings.

  8. 958
    Patrick 027 says:

    Peter Martin (944) – ” However, it’s not so much that they have learning disabilities. I’ve known very competent people, in their own right, who believe in ‘Young Earth Creationism’ and therefore reject the fossil record.”

    If you’d like to do a psychological case study of EXTREME denial, see my conversation with Gord (squashed pumpkin for brains, pun intended) here:
    http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm (starts on p.11 and goes on and on and on through p.21)
    The guy can’t even accept basic arithmetic or cause-and-effect concepts, yet somehow knows about Poynting vectors. Fascinating, frustrating, mind-numbing, and a little scary. It would take a professor from the planet Krypton, with Jedi mind tricks and the patience of Job, to teach him anything.

  9. 959

    #955 Kevin McKinney,

    I react to your, “– the whole point is for everybody to contribute a tiny fraction of what is needed.”

    The important test is whether (the number of said everybodies) times (the tiny fraction of what is needed) equals (something roughly close to what is needed.) (Parentheses are added to give this test a mathematical flavor.)

    Manacker’s point has to be acknowledged, but the solution to the problem is to find economic ways to proceed. In particular, his cost conclusion based on nuclear indicates one wrong way to do it. He might also be right on wind and solar costs, which would say these also are not real solutions.

    Low cost answers like, maybe, insulation? Even that is not quite as low cost as some would like to have us believe. Construction costs do not seem to be correctly represented in some of the arguments I have heard. The reality comes in when a specific proposal is costed out, and I am one of those who has found the results disappointing.

    I see more hope in taking on the problem with engineering solutions that change some of the fundamental ways we do things. We could still ride fast in cars and haul freight if we just insisted on efficiency measures that are far more effective than are now contemplated. We could do quite a lot with rearranging the way we generate electric power from fossil fuels. Some things will look different doing them my way, but you can get an idea what might work looking at my plan (click my name). (My truck projects are not yet shown.)

    We would need to look carefully at our assumptions of what is important, and discard some of the trivial things.

  10. 960
    Patrick 027 says:

    957: “How much sense does it make to capture energy via relatively expensive and cumbersome means thereby converting it into a form of the very highest quality, only to convert it into low quality heat? Why would we take the output of PV and wind generation systems and use it for the very crude requirement of heating water when the heat we want is much more cheaply available? Wouldn’t we want to save the high quality energy for duties such as motive power?”

    YES!

  11. 961
    Doug Bostrom says:

    #959 Jim:

    “Low cost answers like, maybe, insulation? Even that is not quite as low cost as some would like to have us believe. Construction costs do not seem to be correctly represented in some of the arguments I have heard.”

    Handled in the construction phase as opposed to retrofit there are large, inexpensive improvements available.

    The devil is in the details. Anybody who has worked closely with a builder knows two things: getting builders to shift their habits even slightly is very difficult, and getting systems (insulation, hermetic aids, etc.) done correctly is also very hard. Builders are very afraid of callbacks and once they’ve found something that works well enough they stick with until retirement. Systems people work in haste and don’t read instructions. These two things are nearly lethal to getting cutting-edge thermal performance from a new building. Countering them requires the services of truly neurotic architects and Captain Bligh style supervision and inspection.

    With regard to adequacy of work performed, the building trade is kind of the same as nuclear power plant construction. How many abstentious welders living in perfect domestic bliss, never suffering from insomnia and with excellent training do we have available? Enough? Not according to the record of fines and delays…

  12. 962
    James says:

    Barton Paul Levenson Says (3 July 2009 at 6:02):

    “So explain the fact that 42% of the new generating capacity installed across the USA last year was wind.”

    Large tax credits, combined with not much other generation being built? A bare 42% may sound good, but 42% of what total?

  13. 963
  14. 964
    Rod B says:

    PeterMartin (944), I know I seem to keep nit picking. But you guys really should minimize your outrageous side commentaries. There are about 2.5 million deaths annually in the US. How can “…Millions die annually in the USA alone due to particulate pollution caused by the burning of fossil fuels….”??

  15. 965

    Might the confusion about clouds be at the second derivative level? As in, adding more clouds doesn’t result in a linear increase in retained energy.

    This sort of error seems to happen often with the denialosphere crowd. For example, CO2 levels during the carboniferous period were much higher and yet — here we are today, the oceans didn’t boil off, etc.

    There are clearly a lot of cases where the 2nd derivative effect of some climate driver or other is negative, and I’d bet money that’s why the denialosphere is so hung up on “negative feedback”.

  16. 966

    Jim,

    A lot of small fixes really do add up. We’ve been battling 100*F+ days for a while now. All the “small fixes” I’ve made to my house, ignoring the added solar production, cut my summer electric consumption in half (solar takes another huge bite out of it, so my bills are 25% of 2 years ago). “Half” is a lot, and I’m a profligate waster now that I have these tiny electric bills. The areas for further improvement at my house are legion — I’ve not even touched insulation yet, and I already know I have too little.

    There are many environments where energy is just flat-out wasted. High bay halogen lights all over a grocery store during the day? Oh, come on. So much fluorescent lighting in many offices that employees have to use anti-glare screens to cut it down? The list just goes on and on.

  17. 967
    Rod B says:

    Doug Bostrum (957), a quick clarification so it doesn’t get misunderstood: water heating takes 20% of residential energy use (still major), not of total domestic energy use. (assuming you meant domestic to mean the normal national.)

  18. 968
    Hank Roberts says:

    Rod B does the usual plea for homework help

    > How can [whatever ...]

    showing his usual faith in the kindness and intelligence of others, assuming that asking some guy on a blog is a good way to get reliable information (or perhaps that it’s a good way to get information that can be ignored?)

    However, Rod, I will continue to recommend the alternative.
    You can look this stuff up for yourself.

    http://scholar.google.com/scholar?q=%22million+deaths+annually%22+%22air+pollution%22
    Results … about 244

    If you did look it up yourself, you might find it easier to believe the answers you find even if they challenge your political base.

    Oh, wait ….

  19. 969
    Hank Roberts says:

    PS, and here’s the point of looking this stuff up (by the way, Rod’s right that looking stuff up before posting it is a better approach than asking the reader to look it up for you and correct your mistakes — although the latter has been an acknowledged Internet Tradition since USENET at least).

    You can find out what the source is by measuring sources, e.g.
    doi:10.1016/j.chemosphere.2003.07.004
    “… PM2.5 (particles with aerodynamic diameters less than 2.5 μm) chemical source profiles applicable to speciated emissions inventories and receptor model source apportionment are reported for geological material, motor vehicle exhaust, residential coal (RCC) and wood combustion (RWC), forest fires, geothermal hot springs; and coal-fired power generation units…”

    You can correlate the source or the composition — this is fairly new science, going beyond just the particle size that’s now regulated (as PM10 or PM2.5 for example), e.g.
    doi: 10.1164/rccm.200808-1240OC
    “… Communities with higher PM2.5 content of nickel, vanadium, and elemental carbon and/or their related sources were found to have higher risk of hospitalizations associated with short-term exposure to PM2.5.”

    There’s far more there than worth arguing about in a blog, this is a big area where the epidemiology and the risk are widely published.

    When someone posts some vague generality, look it up. It’s always a good idea to do that.

  20. 970
    BobFJ says:

    Bart Verheggen 899, (I’m still trying to catch-up):
    In response to my 896, in which I wrote to you:
    To a degree, [I agree with you] but with increased alleged importance, you are repeating roughly what I said, which, taking point 4) in isolation, was in full, and with emphasis added:
    (4) Thus, putting aside a few relatively trivial complications, SUCH AS regional weather, and especially rainfall variations, if there is an INCREASE in water content in the atmosphere, it follows that it would have to be because of INCREASED E-T.
    I guess you are making an intuitive statement that conflicts with my intuitive proposal. Would that be correct?

    You responded with:

    It’s not just intuition.

    I was merely pointing out that (a change in) the concentration of any species depends on (a change in) the ratio of its sources and sinks; you seemed to have only considered a change in the source as a cause of the change.

    Sorry, but you are wrong. I clearly stated that I considered “sinks”. The issue is that you appear to be intuitively judging them to be of major significance, whereas I intuitively consider them to be of minor significance.
    I’ve also pointed out that whilst there is a great deal of discussion about clouds and water vapour, I have not seen anything on this topic which is a variable influence on the terrestrial energy budget.

  21. 971
    PeterMartin says:

    RodB,

    You’re not nick picking. You are right. I was overstating the case about deaths from particulate pollution in the USA. I should have said millions die every year worldwide.

    According to:
    http://en.wikipedia.org/wiki/Particulate

    “PM pollution is estimated to cause 22,000-52,000 deaths per year in the United States (from 2000) and 200,000 deaths per year in Europe.”

    Still, that is several orders of magnitude higher than would ever be considered acceptable from pollution caused by the nuclear industry. When arguing for restrictions on the combustion of fossil fuels, a reduction of CO2 emissions isn’t the only consideration.

  22. 972
    BobFJ says:

    Kevin McKinney 952:
    Well, here it is again, NASA’s version of the Earth’s energy budget
    http://eosweb.larc.nasa.gov/EDDOCS/images/Erb/components_erb.gif
    It is only a click of the mouse away.
    Please take the time to study it, and then say if you think this respected source (also others like it) is wrong in principle. (don’t worry about the actual values)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Please remember that I stated that the IPCC version includes a crude depiction of the greenhouse effect, and that this may be confusing for you.

    Furthermore, it is clear that you have some misunderstandings about the physics of EMR, (electro-magnetic radiation), versus those of HEAT. Although these two different forms of energy are typically measured in the same units, EMR is not converted to heat unless its quanta, known as photons, are absorbed by matter. That is to say, individual molecules, if not transparent, absorb some photons, and have their kinetic energy increased.

    Otherwise, EMR can fly around in ANY direction, and at ANY energy level, but unless there is absorption, there is no heating. (no temperature increase)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Here is a simple thought exercise for you to try and understand EMR better; in this case sunlight; using eye protection;
    Take a look at the sun, and you may notice that it appears to be a disc of uniform brightness. However, it is a sphere, which means that only the surface right in the centre is pointing straight at you. (in normal presentation). However, on the circumference, the presentation is 90 degrees away from normal, or pointing away from you. And yet it is just as bright. Why?
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Here is another exercise, in the form of an analogy of electricity for EMR.
    Consider two opposing EMF’s of 12 volts and 9 volts. What is their outcome?
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    If you can understand the above, I could then more easily explain why you have misinterpreted the IPCC image

  23. 973
    James says:

    Hank Roberts Says (3 July 2009 at 14:12):

    “http://www.google.com/search?q=“So+explain+the+fact+that+42%25+of+the+new+generating+capacity+installed+across+the+USA+last+year+was+wind.”

    http://www.google.com/search?q=Define+rhetorical+question
    http://www.google.com/search?q=Define+sarcasm

  24. 974
    James says:

    FurryCatHerder Says (3 July 2009 at 15:41):

    “So much fluorescent lighting in many offices that employees have to use anti-glare screens to cut it down?”

    Or one of my pet peeves, buildings that are so well air-conditioned during the summer that I needed to wear sweaters in my office.

  25. 975
    Chris Dudley says:

    Doug (#957),

    “Why would we take the output of PV and wind generation systems and use it for the very crude requirement of heating water when the heat we want is much more cheaply available?”

    We would do this for the same reason that we take coal out of the ground and rather than delivering it to houses to burn in hot water heaters directly, we throw way 60% of the energy at the power plant and use electricity to heat water in the home. It is more convenient. Using 20% of the output of a home PV system to heat water could also make pretty good financial sense as well if tiered rates are available. The roof space is more valuable as an electricity producing area than a thermal water heating area since one can sell electricity at a high price and buy it at a low price. So, there are reasons why we might go with PV entirely (modulo the grid tie).

  26. 976
    Hank Roberts says:

    James, of course.

    Know why I try to clarify stuff like that question, no matter whose writing it is?

    Because not everyone is as smart and clever as you are.

    Readers will come to this in the future and not all of them will understand.

    http://archpedi.ama-assn.org/cgi/content/abstract/155/7/807

    “… for average adults. Materials should be written at the 8th-grade level or lower….”

  27. 977
    Patrick 027 says:

    Re Chris Dudley 973 – electricity can be used for heating, but unless it is for very high temperatures, it makes more sense (depending on technology and economics) to use it to run a heat pump, which will move more heat energy than could have been gained by simply converting electricity to heat. But the most efficient lighting overall is daylight, and the most efficient heating overall may often be the absorption of daylight. But we will want electricity, and perhaps the greatest use of roofspace would in many cases (Depending on local climate, building, landscaping, etc.) would involve a mix of skylights and hybrid systems where waste heat from PV (photovoltaic, not potential vorticity) devices is transfered to water. Skylights and perhaps some southfacing windows and … could also pull double duty as luminescent concentrators (picture a UV absorbing layer and a solar IR absorbing layer – each fluoresces the energy at a somewhat longer wavelength that is mostly trapped by total internal reflection and concentrated onto solar cells along the edges).

  28. 978
    Patrick 027 says:

    Re 972: “However, on the circumference, the presentation is 90 degrees away from normal, or pointing away from you. And yet it is just as bright. Why?”

    Because perfect blackbody radiation is isotropic.

    But there actually is some limb-darkenning, because layers of the photosphere that are thin enough to be approximated as isothermal are too thin to have zero transmittance and 100 % emissivity – but the optical path length over a given temperature variation will be longer near the solar disc edge because of the angle of the line of sight with the solar surface’s local vertical – hence the cooler upper layers of the photosphere more effectively block radiation from warmer layers below and replace it with a smaller radiant intensity.

  29. 979
    Rod B says:

    Hank (968), don’t know what you’ve been smoking, but I found nothing close in your referenced Google screen (didn’t waste my time going past the 1st screen) talking about “millions of deaths in the US due to…” And do you have something against my looking up (to double check) the 2.5 million TOTAL deaths annually in the US, which I did? I didn’t ask anybody about this; I just criticized PeterM’s outrageous claim, and evidently now yours.

  30. 980
    Rod B says:

    PeterMartin (971), decent point. Coal spews out a whole bunch of stuff beyond CO2 that’s not particularly good for anyone, like radiation that often exceeds that of nuclear plant background.

  31. 981
    Rod B says:

    BobFJ (972), Like you I have some problems (and some stuff that I don’t fully understand) with the radiation budget images, but I feel obligated to correct a couple of your points. EMR can fly around in any direction; or it can be roughly (or precisely) confined to certain directions; directional microwave and lasers are easy examples. EMR can not “fly around at any energy level”: its energy level is fixed by its frequency or freq. band — in addition to what intensity it was emitted/transmitted. A picky sub-point: the temperature doesn’t rise with the absorption of EMR, only with the transfer of that absorbed EMR energy to kinetic energy through collisions (predominately).

    The Sun is an example of EMR that does fly around in any direction. Make that all directions. So the point in the center sends radiation directly at us, but also off to its side — at the same intensity and energy. Same for the point that we see on the edge. That energy is shooting out at 90 degrees off the normal you mentioned; but it is also shooting out at that points perpendicular — directly at us, with an intensity that is lessened only by the extra distance of one Sun radius it travels toward us. Nobody can easily detect that difference.

  32. 982
    Patrick 027 says:

    Quick update:

    I’ve now got energy density of ores for solar PV to be ~ 5 to 80 times coal. Rough guesstimate for nuclar, based on nuclear electricity supply, annual U input (?), and ore grade 0.1 % (?): maybe 20 times coal. Doesn’t included recycling gains (PV) or breeder reactors (nuclear); also doesn’t include other components (inverters, …, and a whole bunch of stuff for nuclear). Buy the way, if a nuclear fuel cycle could be developed that produces stable isotopes of Au, Pt, Pd, Ag, etc, as ultimate end products, that would be nice. (How would that be done? The precursor isotope would have to be fed in at high speed (relatively) and cycled through, with desired end products taken out after each cycle – simply leaving a batch to build up desired end products risks destruction of same desired end products).

    Energy density of ore is increased by use of coproducts and byproducts.

  33. 983
    Doug Bostrom says:

    # 967 Rod B:

    As I think I’ve been fairly scrupulous in reminding, but thanks.

    #976 Chris Dudley:

    “Using 20% of the output of a home PV system to heat water could also make pretty good financial sense as well if tiered rates are available. The roof space is more valuable as an electricity producing area than a thermal water heating area since one can sell electricity at a high price and buy it at a low price.”

    A good point. Yet, per square foot of roof area, solar hot water heat beats PV until PV reaches perhaps 70% efficiency, currently something like a 50 point discrepancy if we’re being very generous. I dismiss the importance of efficiency, but price is another matter. Comparing “direct” collection versus PV, the price to supply low quality heat to water is dramatically low for direct versus PV.

  34. 984
    Doug Bostrom says:

    #982 Patrick027:

    That is a pretty fascinating perspective. Thank you.

  35. 985

    Patrick writes:

    If you’d like to do a psychological case study of EXTREME denial, see my conversation with Gord (squashed pumpkin for brains, pun intended) here:
    http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm (starts on p.11 and goes on and on and on through p.21)
    The guy can’t even accept basic arithmetic or cause-and-effect concepts, yet somehow knows about Poynting vectors. Fascinating, frustrating, mind-numbing, and a little scary. It would take a professor from the planet Krypton, with Jedi mind tricks and the patience of Job, to teach him anything.

    Tell me about it. I’m engaged in a discussion of AGW on the amazon.com boards, and one guy there insists, over and over again and despite repeated objection and correction, that A) no one can know what the mean global temperature is, and B) the MGT has gone down over the past decade. Both. Repeatedly.

  36. 986
    Chris Dudley says:

    Patrick 027 (#977),

    There are some pretty good advantages to cooling silicon solar panels with water right now since mirrors are less expensive that silicon still. With sufficient cooling, one can run the panels with concentrated sunlight. One way to do this at very low cost is to sightly raise the temperature of a municipal water supply by turning a water tower into a solar tower as well. The warmer water supply cuts down on water heating costs for everyone while the electricity is produced at a fraction of a cent per kWh. http://mdsolar.blogspot.com/2008/03/lux-lucis-tepida.html

  37. 987
    Chris Dudley says:

    Doug (#983),

    A straight efficiency comparison does not really do it. You are also taking up space in the basement with the larger water tank, for example. And, one may want to consider how recently one has reshingled. Solar PV panels last 25 years or more so they should go on a new roof. Solar hot water comes with 5 to 15 year warranties so that might be better if the roof is older. It is going to depend on details of the installation.

  38. 988
    manacker says:

    Mark 928

    You stated:

    “You keep using that word [rational skeptic]. I do not think it means what you think it means.”

    [To which the moderator made a brief comment concerning the reference]

    Let’s use the Wiki definition. That is what I think it means.

    “Scientific skepticism or rational skepticism (also spelled scepticism) sometimes referred to as skeptical inquiry, is a scientific or practical, epistemological position in which one questions the veracity of claims lacking empirical evidence.”

    What do you think it means?

    Max

  39. 989
    Hank Roberts says:

    > http://mdsolar.blogspot.com/2008/03/lux-lucis-tepida.html

    Wow. Chris, that’s very interesting.
    Have you looked at numbers for doing it on a single house-size scale? Obviously it’s smarter and easier to build in the town size.
    Do look at what grows inside hot water heaters though; pipes might get more biofilm if the municipal system was run warmer. Some chemicals and maybe lead might also leach more into warmer water.

    It’d be fascinating to build a home setup — removing the issues of how the municipal water system handles warmer water — and measure and track how putting the pieces together this way combines efficiencies.

    Placing the water to extend the lifetime of the cells by blocking cosmic rays is brilliant. (The cited paper is now behind a $1.99 paywall at IBM: JRD 42-1 p. 117ff 1998, J. F. Ziegler, Terrestrial cosmic ray intensities. Maybe there’s another source for that info?)

  40. 990
    manacker says:

    Peter (944 and 971)

    WHO tells us that there are close to 2 million people in underdeveloped nations that have no domestic source of energy who die from smoke inhalation from indoor wood fires for cooking. These would be part of your “millions” statistic, which is undoubtedly correct.

    I also fully agree with your position that nuclear (fission) power generation is safe and environmentally sound today. It is also viable economically as a major source of power, as the example of France has shown, but it can be beaten economically on a local basis and at a much smaller scale under special conditions.

    The addition of thorium fast breeder technology could be a step in reducing the nuclear waste problem; at its best a fast breeder reactor produces no waste whatsoever.

    A longer-term solution could come from nuclear fusion.

    But I also agree with your position that the problem has become more political than technical or economic today.

    Max

  41. 991
    Patrick 027 says:

    … oh, I forgot – which isotopes of U are used in nuclear reactors? This could reduce the effective ore grade.
    (Maybe isotopes could be dissolved in the cooling fluid that runs through the reactor core, that are converted into precious metals (or other rare elements that could be useful in solar power, …) and then precipitate out when cooled by the the fluid that drives the turbine. But if this to be an energy-producing step, the precursor isotopes would generally have to be heavier – so there would be more potential pathways to end up with Ag, Pd, Rh, Ru, In, Te, Se, Ga, Ge, Ni, Xe, He than with Au, Pt, Ir, Os, Re. But maybe this would be a good way to dispose of ‘excess’ Hg, Pb, and As, and nuclear waste. Pathways might perhaps include ‘symbiotic’ nuclear fuel cycles – would some produce neutrons, some produce alpha particles, and some produce positrons? Of course, the most energy per unit mass would come from nuclear fuel cycle networks that produce mainly end products near Fe (side to side) on the periodic table.)

  42. 992
    Doug Bostrom says:

    #987 Chris Dudley:

    “A straight efficiency comparison does not really do it. You are also taking up space in the basement with the larger water tank, for example. And, one may want to consider how recently one has reshingled. Solar PV panels last 25 years or more so they should go on a new roof. Solar hot water comes with 5 to 15 year warranties so that might be better if the roof is older. It is going to depend on details of the installation.”

    For sure you’re right, there are many factors to take into account.

    The relatively severe under-performance of PV for heating water compounded by an even larger disadvantage in $/watt is hard to overcome. We could easily replace solar hot water systems at twice the rate of PV systems and come out ahead in terms of operational costs versus energy captured.

    As to space requirements, saving a few cubic feet of basement space and losing all that energy seems like a poor tradeoff. Definitely in my case; the basement space would instantly fill up with junk. Besides, inverters and ancillary gear for PV though smaller than a tank end up taking pretty much the same footprint, if you think about it.

    But again you’re right, it’s easy to oversimplify and overlook.

  43. 993
    Hank Roberts says:

    Rod, when someone makes an outrageous claim, remember the kids who will come along and read your reply later. Give the person making the claim an example of how to check what they believe by looking it up — the particular one, when you look up the links, shows associations with lots of problems. You can decry the single number stated, sure — and he should have cited a source.

    When you catch someone doing that, rather than just scoff, you can also give a good example for later readers: point to better numbers and the range of uncertainty.

    Just asking you to think of later readers and make the effort to add cites along with your skepticism. It furthers the conversation in the longer term, as people read what you write weeks or months later.

    The research on air pollution and health effects makes one think about uncomfortable evidence that the problem is widespread and small particle pollution, particularly from coal and diesel, increases death rates not only directly but more so indirectly by worsening the damage from tobacco, heart damage, and other problems.

  44. 994

    In re Photovoltaics versus Solar Hot Water –

    As Doug pointed out in 983, using thermal collectors to produce hot water (and space heating) is far more efficient than using photovoltaics (PV) (heh) to produce electricity, then use that to produce heat.

    HOWEVER, solar thermal has storage problems. For space heating, passive solar is, I think, a much better solution. That just leaves hot water, which is a much more tractable problem.

  45. 995

    Doug @ 992:

    Inverters and other gear have a major advantage over hot water storage — it can be mounted on a wall and take up precious little floor space.

    One mistake you did make about water is that thermal storage can be buried outside. I’ve toyed with the idea of using a 1000 gallon cistern as thermal storage, then cooling the water before landscape use (obviously I’d use the cistern for pre-heating hot water, but the main purpose for the cistern would be solar thermal storage). That would allow one to store a large thermal mass, then go through the much simpler task of cooling the water that doesn’t need to be kept hot.

  46. 996
    James says:

    Rod B Says (3 July 2009 at 22:42):

    “And do you have something against my looking up (to double check) the 2.5 million TOTAL deaths annually in the US, which I did? I didn’t ask anybody about this; I just criticized PeterM’s outrageous claim…”

    But what you didn’t do, apparently, is to search for a more realistic number: http://www.google.com/search?q=united+states+deaths+from+air+pollution (if I can take a page from Hank’s book). A quick skim gives a range around 30,000-70,000.

    I think PeterM’s error may have been using a world figure for the US. At least the WikiPedia article here http://en.wikipedia.org/wiki/Air_pollution says “The World Health Organization states that 2.4 million people die each year from causes directly attributable to air pollution…”

  47. 997
    manacker says:

    Barton Paul Levenson (951) tells us that 42% of new power generation in the USA in 2008 came from wind, apparently citing a report from the American Wind Energy Association.
    http://www.awea.org/newsroom/releases/wind_energy_growth2008_27Jan09.html

    Other estimates put this at 28.8% globally
    http://www.greencarcongress.com/2009/02/global-wind-pow.html
    http://www.worldwatch.org/node/6103

    Whichever estimate is used, the growth rate is impressive.

    But it should be kept in mind that (according to the BP Statistical Review of World Energy June 2008), global electricity generation in 2007 was around 20,000TWh, and the 2008 wind-generated production would represents 1.31% of that.

    And it should be kept in mind that the on-line factor for wind plants is at most 30%, as compared to 90+% for thermal or nuclear generation, so the actually produced MWH from wind would only be around 0.4% of the total.

    But still, the growth rate is impressive, but we shouldn’t exaggerate the overall importance of wind generation. It is still a very long way from being a major factor globally.

  48. 998
    Hank Roberts says:

    manacker Says: 3 juillet 2009 at 4:35 AM
    > Bob_FJ Thanks for post #939 [now 940, 2 juillet 2009 at 6:45 PM]

    referring to where Bob_FJ writes:
    >> Max,
    >> Concerning peer reviewed publications of Andrew Dessler…. Water
    >> vapour positive feedback, and Roy Spencer; significant negative
    >> feedback clouds, I have the following info:
    >> Dessler … 2008.
    >> Spencer … 2007.
    >>
    >> Is there something new, more significant, and unpublished
    >> by Roy Spencer?

    Yes.

    http://www.grist.org/article/Looking-for-validation/

    The problem with climate-model criticism
    Posted 10:08 AM on 25 Feb 2009
    by Andrew Dessler

    “I have a paper [ http://geotest.tamu.edu/userfiles/216/dessler09.pdf ] in this week’s Science discussing the water vapor feedback. It is a Perspective, meaning that it is a summary of the existing literature rather than new scientific results. In it, my co-author Steve Sherwood and I discuss the mountain of evidence in support of a strong and positive water vapor feedback.

    Interestingly, it seems that just about everybody now agrees water vapor provides a robustly strong and positive feedback. Roy Spencer even sent me email saying that he agrees….”

  49. 999
    Doug Bostrom says:

    #994, 995 FurryCatHerder:

    Just to be extra-clear, which I’m often not, I’m speaking of domestic hot water for delivery from faucets, into dishwashers, etc., a sink representing 20% of residential energy consumption. I’m not speaking of space heat.

    I’m also speaking of pragmatically not attempting to consistently produce finished hot water, but instead raising the temperature of water entering a moderator tank as much as is possible and safe, thus reducing the work done on the water by a downstream conventional heating system. This arrangement is nothing I thought of, it’s a very common choice for people wishing to avail themselves of less expensive hot water.

    A moderator tank properly installed in a non-hobbyist arrangement ahead of a conventional tank-style water heater of whatever type roughly doubles the foot print of the hot water supply. I really don’t see this as a compelling reason to ignore the advantages that thereby accrue by exploiting the low-hanging benefits on offer in the case of domestic hot water energy input.

    Further hopefully clarifying what I’m driving at, domestic hot water represents a special case that deserves a very hard look and possibly special treatment.

    How is it special?

    –Compared to obtaining the electrons needed for so many household activities, heating water via sunlight is extremely easy.

    –A dollar spent on solar domestic hot water heating is astonishingly more effective than a dollar spent on PV, up until the point that domestic hot water conventional energy requirements are being usefully offset.

    –At the same time, domestic hot water represents a sufficiently large fraction of residential energy consumption that, in combination with the ease of substitution by solar for other energy sources for this task, it’s quite possibly worth peeling off from the main energy demand of a household and treating differently.

    Now the engineer in me likes simplicity. I like the idea of a sole source for power because it reduces complexity. But the pragmatist in me cannot help but point out the sorrowful waste involved in sticking rigidly to the ideal of simplicity and thereby losing substantial benefits. My own conclusion is that this is probably one of those cases where we need to bend a little bit because the payback for so doing is in fact truly compelling.

    I fear this diversion or sidebar is taking up too much real estate here, I think I’ve said what I need to say about it, so unless some egregiously stupid remark appears about the topic I’m going to pipe down about it now.

  50. 1000
    Doug Bostrom says:

    Immediately breaking my promise but I hope with good reason, for the curious, cheap, idealistic or some combination thereof here are two really great sources of information about getting work from sunlight, wind, etc.

    A vast collection of mostly DIY oriented “alternative” energy information and projects, ranging from the sublime to the ridiculous but very well run:
    http://www.builditsolar.com

    A professionally operated journal also with a huge range of interesting systems, more oriented to turnkey:
    http://www.homepower.com

    These sites describe many ways to make incremental differences that are sometimes quite large and selectively applied add up to surprising numbers of kWh. Whether you’re down with facts or are having a hard time mentally integrating AGW, don’t let the nattering nabobs of negativism deter you from doing something about our predicament or just cashing in. If you understand the AGW science and don’t like the predicted outcome, you’ll find a physical, real-world response to your anxiety about climate change therapeutic. If you’re can’t understand the science and don’t find cause for concern, let parsimony be your guide.

    Fooling around with some the projects described at builditsolar is a great way to spend time w/your kids, by the way. I promised -my- son a shade tree hovercraft, so far he’s helped put together a solar hot water system and seems perfectly happy for the time being. I’ll probably have to make good sooner or later…

    And that is all from me on this for the time being, hopefully.


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