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Aerosol effects and climate, Part II: the role of nucleation and cosmic rays

Filed under: — group @ 15 April 2009 - (Italian)

Guest post by Bart Verheggen, Department of Air Quality and Climate Change , Energy research Institute of the Netherlands (ECN)

In Part I, I discussed how aerosols nucleate and grow. In this post I’ll discuss how changes in nucleation and ionization might impact the net effects.

Cosmic rays

Galactic cosmic rays (GCR) are energetic particles originating from space entering Earth’s atmosphere. They are an important source of ionization in the atmosphere, besides terrestrial radioactivity from e.g. radon (naturally emitted by the Earth’s surface). Over the oceans and above 5 km altitude, GCR are the dominant source. Their intensity varies over the 11 year solar cycle, with a maximum near solar minimum. Carslaw et al. give a nice overview of potential relations between cosmic rays, clouds and climate. Over the first half of the 20th century solar irradiance has slightly increased, and cosmic rays have subsequently decreased. RC has had many previous posts on the purported links between GCR and climate, e.g. here, here and here.

The role of ions

The role played by ions relative to neutral (uncharged) molecules in the nucleation process is still very much under discussion. For instance, based on the same dataset, Yu and Turco found a much higher contribution of ion induced nucleation (to the total amount of particles produced) than Laakso et al did. Evidence for a certain nucleation mechanism is often of an indirect nature, and depends on uncertain parameters. Most literature points to a potential importance of ion induced nucleation in the upper troposphere, but the general feeling is that neutral pathways for nucleation (i.e. not involving ions) are likely to be dominant overall. Most field studies, however, have been performed over land, whereas over the open ocean nucleation rates are generally lower due to lower vapor concentrations. In theory at least, this gives more opportunity for ion induced nucleation to make a difference over the ocean (even though the ion production rate is smaller).

The ion production rate (increasing with altitude from ~10 to ~50 ion pairs per cubic centimeter per second over land) sets a limit to what the particle formation rate due to ion induced nucleation can be. Based on his model for ion induced nucleation, Yu found that at low altitude, the number of particles produced is most sensitive to changes in cosmic ray intensity. At first sight, this may be a surprising result in light of the increasing cosmic ray intensity with increasing altitude. The reason is that high aloft, the limiting factor for particle formation is the availability of sulfuric acid rather than ions. Above a certain GCR intensity, increasing ionization further could even lead to a decrease in ion induced nucleation, because the lifetime of ion clusters is reduced (due to increased recombination of positive and negative ions). In contrast, at low altitude particle formation may be limited by the ionization rate (under certain circumstances), and an increase in ionization leads to an increase in nucleation.

How important is nucleation for climate?

Different modeling exercises have been performed to investigate this question. The strong dependency on input data and assumptions used, e.g. relating to primary particle emissions and nucleation parameterizations, and the different sensitivities tested, hampers an overall assessment. However, it is clear that globally, nucleation is significant for the number of cloud condensation nuclei (CCN) e.g. in the absence of boundary layer nucleation, the number of CCN would be 5% lower (Wang and Penner) or 3-20% lower (Spracklen et al.), and in a recent follow up study, they concluded that the number of cloud droplets would be 13-16% lower (in 2000 and 1850, respectively). Pierce and Adams took a different approach and looked at the variation of predicted number of CCN as a result of using different nucleation schemes. The tropospheric number of CCN varied by 17% (and the boundary layer CCN by 12%) amongst model runs using different nucleation rate parameterizations. Note that the globally averaged nucleation rates differed by a factor of a million (!).

It should be noted that the sensitivity of the number of CCN to nucleation depends greatly on the amount of primary emissions and secondary organic aerosol (SOA) formed. These are very uncertain themselves, which further limit our ability to understand the connection between nucleation and CCN. If there are more primary emissions, there will be more competition amongst aerosols to act as CCN. If more organic compounds partition to the aerosol phase (to form SOA), the growth to CCN sizes will be quicker.

Locally, particle formation has been observed to contribute significantly to the number of CCN; the second figure in Part I gives an example of freshly nucleated aerosols which grew large enough to influence cloud formation. Kerminen et al observed a similar event, followed by activation of part of the nucleated aerosols into cloud droplets, thus providing a direct link between aerosol formation and cloud droplet activation.

How important are cosmic rays for climate?

At the recent AGU meeting (Dec 2008), Jeff Pierce presented results on the potential effects of GCR on the number of CCN (their paper at GRL (sub. required)). Two different parameterizations for ion induced nucleation were used (Modgil et al and an ‘ion-limit’ assumption that all ions go on to form a new particle). They ran their model with both high and low cosmic ray flux, simulating conditions during solar maximum and minimum, respectively. This happens to be comparable to the change in cosmic ray flux over the 20th century (mostly confined to the first half), and amounts to a 20% change in tropospheric ion production. With both mechanisms of ion-induced nucleation, this leads to a 20% change in globally averaged particle nucleation, but only to a 0.05% change in globally averaged CCN. The authors concluded that this was “far too small to make noticeable changes in cloud properties based on either the decadal (solar cycle) or climatic time-scale changes in cosmic rays.” To account for some reported changes in cloud cover, a change in CCN on the order of 10% would be needed. More studies of this kind will undoubtedly come up with different numbers, but it’s perhaps less likely that the qualitative conclusion, as quoted above, will change dramatically. Time will tell, of course.

The bottom line

Freshly nucleated particles have to grow by about a factor of 100,000 in mass before they can effectively scatter solar radiation or be activated into a cloud droplet (and thus affect climate). They have about 1-2 weeks to do this (the average residence time in the atmosphere), but a large fraction will be scavenged by bigger particles beforehand. What fraction of nucleated particles survives to then interact with the radiative budget depends on many factors, notably the amount of condensable vapor (leading to growth of the new particles) and the amount of pre-existing particles (acting as a sink for the vapor as well as for the small particles). Model-based estimates of the effect of boundary layer nucleation on the concentration of cloud condensation nuclei (CCN) range between 3 and 20%. However, our knowledge of nucleation rates is still severely limited, which hampers an accurate assessment of its potential climate effects. Likewise, the potential effects of galactic cosmic rays (GCR) can only be very crudely estimated. A recent study found that a change in GCR intensity, as is typically observed over an 11 year solar cycle, could, at maximum, cause a change of 0.1% in the number of CCN. This is likely to be far too small to make noticeable changes in cloud properties.

309 Responses to “Aerosol effects and climate, Part II: the role of nucleation and cosmic rays”

  1. 101
    MarkB says:

    Re: #95,

    John Burgeson,

    The good news is that 47% is also up from 41% in June 2006. Although the press release is new, it references a survey from about a year ago:

    This study compares public opinion with scientific opinion on the issue:

  2. 102
    manu says:

    “Note to anonymous commentators: it’s clear that ignores solar, wind and biofuel energy, which really are the only plausible large-scale replacements for fossil fuels.[…] they have resorted to deceptive tactics which appear to be aimed at “solving climate” but in reality simply provide cover for business-as-usual[…]”.Ike,

    No Ike, what “is clear” is that you have no argument to sustain your prejudiced opinion based on 2 min googling of internet archives (or Wayback Machining). Your blatantly misleading quote prove only that you did not understand what you’ve read (or did not want to). Their position on the need for the US to ratify international agreements and do their part is clear, their position concerning the “deception” of the “clean coal” is clear, their position for a need to mandate increases in energy efficiency is clear, their position for an increase in the share of renewable energies is clear, their endorsement of IPCC and Union of Concerned Scientists conclusions is clear.

    What is not clear is why you think they support business as usual to follow a secret fossil energy industry agenda.

    As for them ignoring solar:
    or wind:

  3. 103
    Richard Ordway says:

    Re 60. R. Keene.

    Hi R.,

    I have read your recent edition of the book Skywatch West and listened to one of your lectures to CU college students.

    I suggest that you submit your interesting figures on climate change that I saw to peer review so we can get a feeling of where everyone is.

  4. 104
    SecularAnimist says:

    Wilmot McCutchen wrote: “… storage is an unsolved problem.”

    Storage is not an unsolved problem. We have plenty of technologies for storing energy, including compressed air, pumped water, flywheels, batteries and hydrogen. It’s true that these technologies have not been widely implemented yet. That doesn’t mean that they don’t exist or cannot be deployed at least as rapidly as CCS for coal-fired power plants.

    Moreover, the need for storage in a renewables-based grid is exaggerated. Multiple studies have found that a diversified, regional portfolio of renewable electricity generation including wind, solar, geothermal and biomass can produce baseload power that is at least as reliable as coal.

    Wilmot McCutchen wrote: “The grid becomes unreliable if renewables are more than 20%.”

    That is one of many problems with the existing grid. Which is why every serious proposal for dealing with our energy needs, whether with renewables or nuclear or even just to keep doing what we are doing now, recognizes that we need a major upgrade of the grid.

    And the proposals for a “smart grid” that are integral to every proposal for a completely or mostly renewables-based system all focus on making the grid able to handle diverse, centralized and decentralized, large and small, baseload and intermittent, electricity producers.

  5. 105
    william says:

    #79 Ike
    James Hansen would not agree with your assumption that solar, wind and biofuel energy are the only plausible large-scale replacements for fossil fuels.
    Mr. Hansen suggests 3rd Generation Nuclear plants (IFR+LFTR) are the realistic answer to replace coal.
    I would agree with him and suggest we get on board to support a crash building program of these modern nuke technologies or sit back and watch the Chinese do it while our powergrids brown-out on cloudy or windless days.

  6. 106
    Rod B says:

    a minor secondry question. Do most CRs hitting Earth come from our Sun? near all??

  7. 107
    bsneath says:

    “Time will tell, of course.”


  8. 108
    John H. says:

    Mark 17 April 2009 at 7:57 AM
    “But so complex that no computer model can simulate the broad-picture? If this were true, modern aircraft would be falling out of the sky because they are designed by computer model.”

    Wow what a giant leap.

    But thanks for inadvertently making one of the skeptic’s most germane points.
    Unlike computer modeling for modern aircraft which gets proven with built aircraft being tested and perfected, AGW computer models have no such testing or validation available. Yet AGW modeling is treated by Mark, et al, as if it is as reliable as test computer modeling?

    Mark’s suggestion that AGW computer modeling is as reliable as modern aircraft computer modeling speaks volumes.
    Read my mind for more.

  9. 109
    Ike Solem says:

    For those who claim that renewables do not have storage solutions, please see Germany’s prototype approaches using wind, biogas and solar:

    Likewise, how do you think all the off-the-grid locations store power for use at night? Do satellites go off-line when they traverse the night side of the Earth?

    A real list of “solutions for climate” would include:

    1) A clearly stated goal: elimination of fossil fuel combustion and replacement with renewable energy sources.

    2) A scientific description of the renewable energy sources, distribution systems and energy storage facilities that would be needed – solar, biofuels, wind, and tidal.

    3) A plan for setting up a technologically advanced fossil fuel-free agricultural system that also involves good water conservation – solar electric tractors, biohydrogen-based fertilizers, etc.

    4) A plan for providing industrial-strength renewable energy solutions for major critical industries, especially steel and cement production, but also for other manufactured goods.

    5) A plan for replacing global fossil-fueled transportation systems with renewable energy-powered transportation.

    6) Plans for dealing with inevitable climate change – at the top of the list are water conservation and management for drought, sea wall engineering for low-lying areas.

    By the way, no one is ever going to beam solar to Earth – the costs would be ridiculously high, for one thing, and what if the “energy beam” (what is this, Buck Rogers?) drifted off-target? We already know how to build 1 GW solar thermal plants, after all.

    Getting back to aerosols: see the DotEarth discussion on the recent paper on Atlantic forcing of African droughts:

    Is there still an ongoing debate over whether global warming is natural or anthropogenic? That title sure seems to indicate that there is still a “valid controversy”.

    Let’s review one possible mechanism for locking African droughts into megadroughts: as the Sahel dries up, more dust is produced. The dust goes out over the Atlantic, cooling SSTs. Cool SSTs force more drought… or do they? Perhaps SSTs only indirectly exert effects via influencing shifts in atmospheric circulation… which is also sensitive to land-atmosphere feedbacks. Does this indicate a complicated feedback loop between dry conditions, expansion of the Sahara, and Atlantic SSTs (at least in West Africa)?

    Brian Fagan says this in his recent book, “The Great Warming”

    “Today, climate in the Sahel leaps abruptly and without warning from one mode to another in a completely unpredictable manner.”

  10. 110
    Ray Ladbury says:

    Rod, When we are talking about cosmic rays energetic enough to interact with Earth’s atmosphere, we are talking almost exclusively about Galactic Cosmic Rays(GCR). GCR are accelerated by shock waves of supernovae and have a median energy of about 1 GeV (equivalent to a proton mass) per nucleon–thus, they have about as much kinetic energy as mass-energy. GCR fluxes are on the order of 5 particles per square cm per second. The highest fluxes occur when the solar wind is weakest (solar minimum) and the lowest at solar max.
    Most solar particles get trapped by geomagnetic field lines and for the Van Allen Belts of trapped particles. Eventually they spiral toward Earth’s poles and interact with oxygen and nitrogen in the far reaches of the upper atmosphere, producing aurorae. Only the biggest solar particle events produce particles energetic enough to penetrate even into the upper atmosphere. The Carrington event (1854) produced aurorae visible as far south as Havana! Hope that helps.

  11. 111

    Do most CRs hitting Earth come from our Sun? near all??

    Near none if not absolutely none. Nothing the Sun is known to do can produce particles with 1 GeV or more of kinetic energy.

    (How fire can be domesticated)

  12. 112

    “The grid becomes unreliable if renewables are more than 20%.”


    No, the grid becomes very EXPENSIVE if renewables are more than 20%. However, that is very old news and there have been enough solutions over the past few years (including a few patents I’ve filed myself) to make that limitation go away.

    On topic …

    The current GCR count is at an all-time high since 1964 according to the Oulu website that’s been mentioned, so I’m unclear where the “hasn’t changed much” claim comes from.

  13. 113
    dhogaza says:

    Mark’s suggestion that AGW computer modeling is as reliable as modern aircraft computer modeling speaks volumes.
    Read my mind for more.

    Reading … reading … your mind is empty.

    Aircraft modeling is more akin to weather modeling than climate modeling, and we know which is more accurate.

    Yet … modern airplanes fly.

  14. 114
    Mark says:

    “AGW computer models have no such testing or validation available.”

    Yes, they do.

    You see, what happens is that there are AT LEAST two ways of validating the model:

    1) Run for a different period in the past. Start up with a known profile from the past. Let the model run. Does the subsequent change in the model reflect the historic record of what happened next?


    Then it’s physically realistic. Tested.

    2) Run for the future. Start off with today’s weather. Wait. Did the model match what really happened? If yes, then it’s physically realistic.


    Now, why do you think that the models aren’t tested?

    Merely because you BELIEVE with all your heart and soul that AGW is a myth. Anything that could back that assertion up is accepted as gospel.

  15. 115

    Wilmot McCutcheon writes:

    Renewables (with the possible exception of concentrating solar) are not suitable replacements for coal as baseload power because renewables are intermittent and storage is an unsolved problem. The grid becomes unreliable if renewables are more than 20%.

    Do you have a source for these assertions?

  16. 116
    Mark says:

    Of course Wilmot doesn’t. If he had one, it would be a solid statement that can be tested for truth of falsity. So it’s better not to have a source and just assert away.

    He isn’t trying to convince you, he’s just trying to put stuff up that will give people who believe the same way a talking point. A talking point where they won’t have to (or be expected to) produce any proof.

  17. 117

    In re #115:


    This had been studied and it was found that at a 20% penetration for renewables, the cost of base power was matched by the costs for the reserves that make the grid function. Since regulatory power reserves are more expensive than base power, minor increases in renewable energy result in significant increases in regulatory power and cost.

    What’s changed is how grid loads are being managed today in a number of regions. The work I was doing before my former employer decided I needed to become self-employed will greatly reduce the amount of regulation the grid needs without all the fancy “Smart Grid” foolishness I often read about.

  18. 118
    Ike Solem says:

    “Since regulatory power reserves are more expensive than base power, minor increases in renewable energy result in significant increases in regulatory power and cost.”

    There’s no such thing as “base power” – that’s just a trick the utilities use to jack up electrical bills. You get so many kWH of “base power”, then you get additional charges for “above baseload” – but all you are doing is buying power. Imagine if you were buying some other product, and you were not given a discount for buying in bulk – you were instead charged more.

    The last thing the utility wants you to do is to generate your own power, because then you don’t pay them anything. In reality, if renewable generation exceeds 20% than an investor-owned private utility becomes unprofitable – except for the owners of the generation systems – and why not? If you are generating power, why shouldn’t you be able to sell it for the same rate that a coal-fired power station does? Just to protect the bottom line of utility-coal-railroad holding companies?

    As far as smart grids, those are better referred to as load-balancing grids – see the youtube video on Germany’s experiment. See any problems there?

    Of course, renewables would also eliminate the problem of black carbon aerosols.

  19. 119
    David B. Benson says:

    FurryCatHerder (112) — We are currently experiencing a deep, protracted solar minimum the likes of which has not been seen since 1913 CE. So one expects a bit more GCR flux.

  20. 120


    I think you’ve demonstrated what you completely don’t know about electric power generation.

    “Base load” is based on day-ahead predictions and is met by large plants that operate most efficiently at either a large and fixed value of output, or at very slowly varying values of output. It’s not some scam to keep you from doing a load of wash on in the afternoon instead of the evening.

    The expensive stuff comes from fast reacting generators that can’t just churn out 100’s of megawatts all day long. They aren’t some ploy to rip you off. They really are more expensive to operate, to some extent because they are less efficient, and to some extent because there are missed-opportunity costs with the unused capacity waiting for someone to turn on their toaster oven, microwave, blow dryer, and vacuum cleaner all at once. That’s why there is a discount for being CONSISTENT. Because if you are CONSISTENT, then the utility can better predict how much power to produce with the cheap generators. It’s when you are INCONSISTENT that you cause the utility to bring more expensive, regulatory generation on-line.

    The problem is also not with self-generation (and I’ve been off-grid 14 out of 18 days so far this month) that they aren’t making money — my neighbors pay about $0.13 / KWH and I paid $0.16 / KWH last month. They make even more money, per KWH generated, off someone like me, than off someone who is grid-connected all the time. My “base” bill is about $9 a month, no matter how little I use. At $0.16 / KWH, that’s the same as 56 KWH I don’t even use, and this time of year I might only use 100 KWH from them — they get to charge me 33% more than my neighbors, per KWH used, and I get to turn them off and have a 100 KWH bill (plus the $9 for being connected) for the month. They charge me for being connected, I get the security of having the grid around when a storm system passes through for a few days, we’re both happy.

    So, the reality of renewable energy generation is far from the conspiratorial gloom-and-doom that shows up on boards like this. It works great, I’ve been doing it at home for nearly two years, I have tiny little electric bills, and I don’t have power outages like my neighbors. Life is truly great in renewable energy land.

    Some of the technologies I worked on, when I was with the Three Letter Company I used to work for, will not only make the grid work better (which is goodness for the utilities), but they will also create partnership opportunities between generators, transmission line owners, retail and wholesale providers, and distributed generation producers. Entire new kinds of businesses are going to emerge, and the different players will be able to create profit centers by doing so. There are many creative ideas going on out there, including some that are fairly sadistic (the IP law team that reviewed one of mine went “Oh, that is MEAN!” when I described one to them) that will shift the burden onto people who insist on being hostile towards the electric grid, while rewarding consumers who cooperate. And why shouldn’t the grid work that way?

  21. 121

    FurryCatHerder, you are being a bit coy about the “many creative ideas going on out there” that the rest of evidently need to know about. Is there some place the rest of us can read about them?

  22. 122
    Ray Ladbury says:

    John H. says, “Unlike computer modeling for modern aircraft which gets proven with built aircraft being tested and perfected, AGW computer models have no such testing or validation available. ”


    Ohhh! Too bad, but thank you for playing!!

    Climate models reproduce the trends of both paleoclimate and the modern climate. They have nailed the effects of perturbations like volcanic eruptions.

    But, hey, if you don’t like the climate models, produce your own. Just try and construct a model tha produces an even vaguely Earthlike climate without a significant CO2 forcing. Go ahead… we’ll wait.


    Sure is quiet.

  23. 123
    Douglas McClean says:

    #31 said:

    “Of course, nuclear provides heat without combustion, but suffers from the need for vast amounts of cold water to cool the reactor and transfer energy to the steam turbine that generates electricity.”

    This cold water (or cold something) is, of course, required for any thermal power source, and is by no means unique to nuclear power. Read it, learn it, love it, because there is no escaping it:

  24. 124
    Douglas McClean says:

    (Of course, you can use an evaporation tower to turn warmish water into coldish waster, as long as the surrounding air is dry enough. The same tricks here, and the same sizing requirements for the evaporation tower, apply to all of the “first, make something hot” schemes of power generation, which is basically all of them except for hydro dams and solar photovoltaics.

  25. 125
    CTG says:

    Um, I’m guessing that the 20% figure relates to the US, and reflects the way that the US Grid has been built. There is no reason that it should not be higher, *if* the grid was designed to cope with it.

    Here in New Zealand, renewable energy (hydro, wind and geothermal) averages about 65% of generation; in December 2008 it reached 74%. Of course, our grid is designed with this in mind, even though there are considerable distribution problems. Most of the hydro power is in the South Island, while most of the people live in the North Island, so the grid has to be pretty efficient at long-distance distribution. If NZ can manage this, I don’t see any reason why the US can’t.

  26. 126
    Will Denayer says:

    Hi, this is OT again, but this is a really interesting article (based on an interview with Obama’s GW chief scientist).
    Andrew Glikson | Toward Climate Geoengineering?
    Andrew Glickson, Truthout: “That global climate change has reached an impasse whereby the ‘powers-to-be’ are entertaining climate geoengineering mitigation, instead of the urgent deep reduction of carbon emissions required by science, represents the ultimate moral bankruptcy of institutions and a failure of democracy.”
    Best, Will

  27. 127

    31 Ike Solem: Nuclear power plants do not necessarily require water for cooling. Nor is water used up in plants that do use water. Air works just as well. It is a matter of choice for the engineers. Waste heat must be dissipated from any heat engine, whether it be nuclear, coal, diesel or gasoline. Your car has a radiator too, unless it has an air cooled engine.

  28. 128
    Keith Strong says:

    I would like to point out that Sunspot Number (or sunspot count) is not a very good measure of solar magnetic activity. Sunspots represent between 0 to 20% of the magnetic filed on the Sun at any given time. Most of the field is too weak to form sunspots.

    A second point is that it is not the sunspots that define the large-scale field of the Sun (the heliosphere) that would be the weaker polar (dipole) field of the Sun coupled with the outflowing solar wind.

    While some claim there is a relation between the polar fields and the size of the upcoming sunspot cycle (e.g., Ken Schatten) that is still highly contriversial in solar cycle studies.

    Thus any correlation between sunspot variability and climate variability (which could at best be termed tenuous) is likely fortutitious or must be ascribed to an alternative mechanism such as variations in total solar irradiance (TSI) rather than cosmic rays.

    TSI variability is linked directly to sunspots and their companion faculae (brighter patches on the visible solar surface). The problem with TSI changes are that they are far too small in terms of energy to explain increased global temperatures (as well as not fitting the global warming finger print very well). We would need some as yet unknown amplification mechanism to make the grade.

    Of course these two could be playing together: Increased solar activity with CR decrease and TSI increases. The only problem with that is that solar activity has been decreasing over the last 30 years.

    Solar Cycle 21 peaked 1978/9 at sunspot number of 165 (annual average)

    Solar Cycle 22 peaked 1989/1990 at a sunspot number of 160

    Solar Cycle 23 peaked 2000 at a sunspot number of 120

    The sunspot number of the solar minima between these peaks is also decreasing.

  29. 129

    To those people who think we have good storage solutions for intermittent sources of electricity: Did you check out the efficiency? or the cost? Or whether we have enough of whatever on the whole planet to make that much or many? Surprise! Your efficiencies may be about 5%, the cost could add $10,000/year to your electric bill, and it is doubtful that we could find that much of whatever on this planet.
    If those intermittent sources really were so good, don’t you think the electric companies would have saved themselves the $100 Billion/year purchase price of the coal they burn in the US alone? Of course they would. It hasn’t happened because the cost of energy storage for intermittent sources is FAR higher than $100 Billion per year. And the intermittent sources are more expensive than coal and nuclear to begin with.
    Nuclear power is 30% cheaper than coal and FOURTH generation nuclear is the safest energy source there is. Did you know that coal contains uranium?

  30. 130
    Mark says:

    “To those people who think we have good storage solutions for intermittent sources of electricity: Did you check out the efficiency? or the cost? Or whether we have enough of whatever on the whole planet to make that much or many?”


    Lead is indefinitely recyclable. Acid for it is indefinitely renewable.

    “the cost could add $10,000/year to your electric bill”

    And just as likely, it could add $0/year to your electric bill. With the source for the energy not having to be bought from another state, you keep your money in YOUR system, meaning that the country has a better trade deficit and so your taxes (to pay off the trade deficit) will reduce, leaving you more money to spend on anything you want. Including more electricity.

  31. 131


    The “renewables” you are including aren’t the ones discussed in the reports that speak about 20+ percent penetration being a problem (except for wind — wind can be a problem, unless the wind power is consistent, as it is in parts of the States). Hydro and geothermal are both very manageable and reliable sources, if one has them. It’s wind and solar that have issues.

  32. 132
    Ike Solem says:

    Wind and solar don’t have technical issues, just political ones related to the existence of fossil fuels in the electricity supply business. Yes, the utilities could convert to solar and wind – but where does that leave the coal mines and the railroads? Those sectors are usually coordinated at another level, something Samuel Insull came up with in the 1920s or so.

    On a more topic-related note, solar and wind also eliminate the warming problem of black carbon aerosols, as the only energy conversion process involved is from photon to electron – no atoms or molecules are involved, so no aerosols are going to be formed.

    Not only that, solar and wind do not need large supplies of cooling water, which is one of the three main drawbacks of nuclear (the others being weapon proliferation and uranium scarcity). Solar is a relatively low-energy power source compared to nuclear – but solar panels don’t shut down when temperatures soar, as do France’s river-cooled nuclear reactors during summer heat waves. Coal-fired power plants also require similar volumes of cooling water.

    In order to develop large-scale renewable generation, a good deal of international cooperation and government support will be needed – the same was true for the international oil business – and government backing for the oil industry has always been portrayed as a critical matter of national security, as compared to government support for renewable energy, which is “proto-communism”, certainly not a national security issue like oil is…

    To do that will require something like the International Atomic Energy Agency, IAEA – The U.S. press just won’t cover the International Renewable Energy Agency, or the refusal of any member of the federal government to back it. It makes one wonder if U.S. states can send individual delegations?

    April 8th, 2009 –

    Dubai, Apr 8 (ANI): The emirate of Abu Dhabi in the UAE, although an oil producer, is considered to be one of the strong candidates for hosting the headquarters of the International Renewable Energy Agency (IRENA) which was officially established in Bonn earlier this year.

    The United Arab Emirates have been actively promoting renewable energy, and Abu Dhabi in particular has launched the innovative Masdar initiative – a pioneering project which will be the world’s first carbon – neutral, zero waste city.

    The statutes of IRENA, the aim of which is to promote dynamically the sustainable use of renewable energy on a global scale, have been signed so far by more than 70 countries. The Agency is expected to play a key role in the world-wide effort to prevent further climate warming.

    There is a similar effort by a private developer in Florida to set up a zero-carbon development – kind of strange, isn’t it, that an oil producing nation like UAE would put government support behind such a project, while the U.S. government steadfastly refuses to even mention the existence of such an approach – look anywhere in the DOE for “zero-carbon city”, for example.

  33. 133

    Tonight (Sunday April 19) CBS 60 Minutes will do a segment on Cold Fusion. I’m fairly convinced that this safe, clean technology will replace oil, gas and coal. I’m an engineer and a long time researcher in this field.


  34. 134
    llewelly says:

    Jeff Driscoll, (#133) please stop mocking engineers.

  35. 135
    Lawrence Brown says:

    Hydro power does have reliability problems, particularly during periods of extended of low flow.For example at Niagara Falls:

    “Several hydropower plants are located at Niagara Falls, New York and Ontario. These plants divert water from the Chippawa-Grass Island Pool above Niagara Falls, and return the water to the Niagara River below Niagara Falls. The amount of water available for hydropower purposes at these plants depends on the Niagara River flow which, in turn, depends on the water level of Lake Erie. The initial work efforts of the study would be focused more on the hydropower generation on the St. Marys River, where changes to Lake Superior regulation would have the greatest impact on hydropower operations. …………………………….
    The amount of hydropower generation on the St. Marys River depends on several factors, the key ones being head, flow, efficiency, tailwater level, river ice and aquatic growth, and meteorological disturbances. Apart from these physical factors, there are other elements that affect hydropower operations……… When the flows are too low, the electricity generated may not meet the demands of the customers and the utilities may have to purchase power from other sources at relatively higher prices. The purchased power may be generated by coal, oil, or nuclear. “

  36. 136
    Mark says:

    And during the oil crisis, there was a reliability problem with oil powered electricity stations.

  37. 137
    James says:

    CTG Says (18 April 2009 at 9:11 PM):

    “Um, I’m guessing that the 20% figure relates to the US, and reflects the way that the US Grid has been built.”

    Not really. It’s down to the way the power system works. Fundamentally, the amount of energy used has to be matched, on a pretty much instantaneous basis, by the amount of energy generated. There’s room for a little slippage – energy gets stored in e.g. the inertia of rotating generators or the electromagnetic equivalents – but everything has to be working close to the system frequency & voltage. This is a lot easier when you have throttles on your generators, and don’t have to accept whatever those wind turbines are producing from however hard the wind’s blowing today.

    “Here in New Zealand, renewable energy (hydro, wind and geothermal) averages about 65% of generation; in December 2008 it reached 74%. Of course, our grid is designed with this in mind…”

    Again, no. The problem isn’t “renewable”, it’s “intermittent”. Hydroelectric generators can be throttled – just let more or less water run through the turbines. Geothermal plants produce a pretty much constant output. Neither presents any problem to the grid – there’s a geothermal plant up the road from me that’s been cranking out 100 MWatts or so for decades.

    Wind’s the problem child here. The amount of energy produced by those wind turbines depends – obviously! – on how hard the wind’s blowing. If you need 100 MWatts, but the wind’s only blowing hard enough to make 50, your system falls apart. What your New Zealand system control operators probably do is to open the spigot on the hydro dams. Having enough hydro (or other throttable generation) to take up the slack when the wind’s not blowing is what lets wind generation work in your system.

    “If NZ can manage this, I don’t see any reason why the US can’t.”

    Because you’ve got a lot more hydro & geothermal potential per capita than the US does. Off the top of my head, it’s about 10% of the total, so we could add in a similar amount of wind/solar without running into grid problems. (Though there’s not a single US grid, but half a dozen regional grids, some of which extend into Canada & Mexico: )

    This is also how the “Denmark gets 20% of its electricity from wind” factoid works. There’s no independent Danish electric grid: it’s all part of a single European grid, so the Danish windmills are supported by French nuclear plants, Swiss hydro, and German coal.

  38. 138
    John Finn says:

    Re: 55 Mark Says:

    John, #53. As gavin said, you seem to be taking the IPCC statement and thinking they’re talking about something they aren’t (artic temps!=global temps) and then saying that because this thing they aren’t saying isn’t true (artic temps not following global temps), then the IPCC got it wrong.

    Sorry, but I must come back on this. Are you saying that the arctic cooling and NH cooling, in general. are unconnected. Without the arctic cooling – there would have been no NH cooling. The arctic cooled by at least 4 times as much as the NH in general.

  39. 139
    Mark says:

    “Fundamentally, the amount of energy used has to be matched, on a pretty much instantaneous basis, by the amount of energy generated.”

    Read up on brown-outs.

    And so energy can be lost anyway.

  40. 140
    Stephanie Gagne says:

    Thank you Bart for the nice review on new particle formation and growth. As you pointed out in previous comments, it’s nice to see that our own research matters and you point out nicely how nucleation in general and ion-induced nucleation in particular matter for the big picture. Your post will be useful to explain to people outside the field what aerosols –and their nucleation- are about and why it is important to understand the processes involved.

    P.S. The link to the work by Laakso et al. directs to the wrong article, the correct link is

  41. 141
    Mark says:

    “Are you saying that the arctic cooling and NH cooling, in general. are unconnected.”

    I’m saying that they are only connected on a climatic scale.

    Think about it. The only way to get warmth to the ice in the south pole (without changing the axial tilt or the solar constant) is to get warm air there.

    The North pole, you can get warm air there or warm water.

    And getting warm air to the south pole isn’t easy: there’s a generally higher pressure and there isn’t a lot of intraining of air into the interior.

    Why do you find that the continental climate of Antartica being poorly correlated to the maritime Artic so difficult? What is the difference between London and Moscow, except one is continental and one is maritime?

    Their climate is severely different.

    Why not here?

  42. 142


    If those intermittent sources really were so good, don’t you think the electric companies would have saved themselves the $100 Billion/year purchase price of the coal they burn in the US alone? Of course they would.


    Nuclear power is 30% cheaper than coal

    “If nuclear really was so good …”

  43. 143
    CTG says:


    I guess it comes down to how you define “renewable” then :-)

    If you define hydro and geothermal as “non-renewable”, then of course the percentage goes down. It seems pretty arbitrary to me to define a power source as “non-renewable” just because it is predictable!

    The point is, most renewable power has lower GHG emissions than non-renewable (I recognise that geothermal is not emission-free). If you can design a grid that gets 75% of its power from renewable sources (however reliable or predictable those sources are), then you are going to have a lot less emissions than grid that can only get 20% from emission-free sources.

    In NZ, thermal generation is mainly used to take up the slack from when hydro can’t meet the whole demand. It does still consume fuel to keep a thermal plant spinning when it is not generating, but a hell of a lot less than when it is going full bore producing power. This is reflected in the spot market for power, where any power above the predicted load is sold for a much higher price.

    All I’m saying is that there is a market where renewable energy sources provide the majority of the power, so people shouldn’t go away thinking that 20% is some “magic” figure for the maximum amount of renewable energy you can put into an electricity grid.

  44. 144
    Ike Solem says:

    Well, you can have 100% renewable – so why don’t we have any plans to build solar cities? Why is the emphasis on band-aid solutions?

    Simple. We pull 500 million tons of coal out of the Powder River Basin each year, ship it by rail to the southern and central U.S., and convert it to 1.5 billion tons of CO2 and many gigawatts of electrical power. If you build zer-carbon renewable cities instead, there is no need for fuel – meaning no need for the coal mines or the railroads.

    Now, you would think think that utilities would be happy about this, because they would no longer need to buy fuel – but they would need to own the power generating system in order to generate profits. At the very least, they would need to control the power distribution system in order to remain financially profitable.

    This creates an interesting situation – who has the right to sell power across the grid? In a true free market, anyone would have access – that would create a competitive situation that would maximize efficiency and minimize costs – unless you think cartels do a better job of that.

    The only reason a number like 20% is offered is because it comes before 40%, which comes before 60%, etc. That’s the same idea behind Kyoto and Copenhagen accords – stepwise reductions in fossil fuel use, to be made up with stepwise increases in renewable energy generation.

    We ought to hurry up, though. Ocean dead zones are looking more likely to expand:

    …”ocean acidification” is not the only way that carbon dioxide can harm marine animals. In a “Perspective” published in the journal Science, Peter Brewer and Edward Peltzer combine published data on rising levels of carbon dioxide and declining levels of oxygen in the ocean in a set of new and thermodynamically rigorous calculations. They show that increases in carbon dioxide can make marine animals more susceptible to low concentrations of oxygen, and thus exacerbate the effects of low-oxygen “dead zones” in the ocean.

    There’s also the synergistic effect of human nitrogen fixation to consider – and this is an area where data collection is very limited.

    The world’s political leaders have too many ties to fossil fuel interests to ever promote real change. Even a political figure like Al Gore can’t bring himself to say that the only way to slow global warming is to eliminate the combustion of fossil fuels. Political leaders instead claim they can build coal carbon sequestration systems, despite fundamental problems – and that applies to places like Stanford University, as well – they claim, with a straight face, that they can capture and bury 90% of the CO2 emissions from coal combustion – on a global basis, no less.

    The simplest thermodynamic and mass-energy balance arguments show this to be false. For example:

    1) One ton of coal leads to about three tons of CO2. That would be the mass component. Second, coal is a solid, and CO2 is a gas – going from CO2 (gas) to CO2 (liquid) to solid carbon requires energy.

    2) That energy will come from the heat produced by the burning coal – but what % of that energy will be required to capture all that CO2? A big coal plant might burn 5 million tons of coal a year, resulting in 15 million tons of CO2 from that facility alone. To capture the all emissions from one ton of coal would require most of the energy provided by that coal – probably close to 90%.

    3) That means your new, high-tech FutureGen coal plant will only generate 1/10th the usable power of a dirty old pulverized coal plant, per ton of coal. It’s a bad joke, a technological farce, a white elephant – and a means for electrical cartels to claim they’re making changes while doing nothing at all.

    This doesn’t keep the liberal green Australian government from making ridiculous claims, even as the country suffers under global-warming induced drought:

    Australia’s Kevin Rudd, professed greenie, has launched a carbon capture institute. This is a government-funded initiative to coordinate and accelerate carbon capture and storage projects worldwide. “Our vision is to build an institute that will galvanize global efforts to demonstrate and deploy CCS technology,” Rudd told the initial meeting of the Global Carbon Capture and Storage Institute (GCCSI) in Canberra, reports NatureNews. “This recognizes the cold hard reality that coal will be the major source of power generation for many years to come.”

    The current U.S. administration’s dedication to coal can be seen in this story on one of their main economic advisers:
    “Warren Buffett’s Berkshire Hathaway Buys Constellation Energy Group Inc., Nalco Holding Company, Burlington Northern Santa Fe Corp. Feb 17 2009”

    That’s a classic energy deal – a coal-fired utility and a railroad to service it. No one is planning on eliminating coal any time soon, as that shows.

    It’s not too surprising, really. Obama’s biggest backer in the Senate was the midwestern utility Exelon, a coal based concern. You’re looking at a situation where midwestern coal cartels and tar sand developers are in the driver’s seat on energy policy, as compared to the previous administration, which had a more Mideastern oil flavor.

    Or, try Barak Obama on the campaign trail:

    “Clean coal technology is something that can make America energy independent!…We put a man on the moon in 10 years. You can’t tell me we can’t figure out a way to burn coal that we mine right here in the United States of America and make it work!”

    Why can’t we find a foolproof cure for cancer? Why can’t we make ourselves live for 200 years? Why can’t we make cold fusion work, and solve all our energy problems forever? Why can’t we engage in telepathic conversations, like in science fiction movies? Why can’t we ride on magic carpets and so solve the transportation issue? After all, we put a man on the moon – now we just need fires that don’t create smoke or carbon dioxide… not possible.

    Is there a real solution? Yes. It’s called the sun. Photon to electron conversion. No carbon or hydrogen or oxygen atoms involved. What is wind? sunlight converted to mechanical motion – no chemical combustion and transformation, no aerosols – just clean electricity. In the future, we’ll run everything off solar and wind, and the fossil fuels will stay in the ground.

  45. 145
    James says:

    CTG Says (20 April 2009 at 8:59 AM):

    “I guess it comes down to how you define “renewable” then

    If you define hydro and geothermal as “non-renewable”, then of course the percentage goes down. It seems pretty arbitrary to me to define a power source as “non-renewable” just because it is predictable!”

    Seems as though you missed the point I was trying to make, which is that in the context of grid stability, renewable vs non-renewable simply doesn’t matter at all. What matters is the degree of controllability, because generation needs to be matched to load.

    Hydroelectric is an example of a renewable that doesn’t present a problem to the grid: the operator just varies the amount of water going through the turbines so the needed amount of power is generated. You could likewise imagine some form of non-renewable that’s not controllable (though I can’t think of one offhand), and that would present the same grid stability problem that wind does.

  46. 146
    Mark says:

    Although over a country as widely spread as the US, the rather fuzzy law of large numbers will ensure that there’s plenty of wind SOMEWHERE.

  47. 147
    Ike Solem says:

    Here is the basic notion behind coal and nuclear power plants and “baseload” and “load following” concepts, from a French nuclear power site:

    “Normally base-load generating plants, with high capital cost and low operating cost, are run continuously, since this is the most economic mode. But also it is technically the simplest way, since nuclear and coal-fired plants cannot readily alter power output, compared with gas or hydro plants. The high reliance on nuclear power in France thus poses some technical challenges, since the reactors collectively need to be used in load-following mode.

    (Since electricity cannot be stored, generation output must exactly equal to consumption at all times. Any change in demand or generation of electricity at a given point on the transmission network has an instant impact on the entire system. This means the system must constantly adapt to satisfy the balance between supply and demand.)

    It turns out that electricity can be stored – but batteries have limits on energy storage density. Still, they can be used. A more ideal storage medium might by hydrogen. A technological possibility is to mimic photosynthesis – usually, that just refers to mimicing the light reactions, the photon-to-electron / water-splitting reactions. However, it might just be easier to grow algae (roughly 50% oil by weight) – but in the long run, we are talking about doing with carbon what Haber and other German chemists did with nitrogen – simply take it out of the air and convert it to whatever carbon-based molecule you need.

    Notice also that coal, nuclear and hydropower all have the same common need: water. No need for water is another main advantage of wind and solar, especially in arid regions like Spain.

    There is no technical reason that wind and solar production in the U.S. could each be quickly increased to the same level as nuclear, leading to an electricity mix of 20-20-20 nuclear, wind and solar. Energy efficiency, geothermal and hydropower (including tidal or wave generation) and more advanced electricity storage technology could then make up the gap without any fossil fuel input.

    Interestingly, the two countries that seem best poised to take advantage of solar are Israel and the UAE, due to a combination of ideal location plus a record of technological and financial investment in solar. Solar desalination in particular is looking like less of a luxury and more of a survival strategy.

  48. 148
    Mark says:

    And the UAE can sell their oil for profit, rather than burn it in their internal market for no profit.

  49. 149

    CCS and Obama, Part I of II

    Ike Solem wrote in 144:

    To capture the all emissions from one ton of coal would require most of the energy provided by that coal – probably close to 90%.

    Personally, I believe that CCS is snake oil, the industrial equivilent of vaporware. However, looking at:

    IPCC Special Report
    Carbon Dioxide Capture and Storage
    Summary for Policymakers
    A report of Working Group III of the IPCC and Technical Summary
    A report accepted by Working Group III of the IPCC but not approved in detail

    … in the table “TS.10. Range of total costs for CO2 capture, transport and geological storage based on current technology for new power plants using bituminous coal or natural gas” on page 40 in the section “Power plant with capture and geological storage: % increase in cost of electricity,” I find the figures of 43-91, 37-85 and 21-78 for “pulverized coal power plant, natural gas combined cycle power plant” and “integrated coal gasification combined cycle power plant,” respectively.

    However, these would appear to be just estimates since at least as of 2007 there has not been so much as a pilot program performed on a large scale.

    Please see:

    It should be noted, however, that CCS has not yet been applied at a large (e.g., 500 MW) fossil-fuel power plant, and that the overall system may not be as mature as some of its components.

    ibid., page 16

    Ike Solem wrote in 144:

    1) One ton of coal leads to about three tons of CO2. That would be the mass component. Second, coal is a solid, and CO2 is a gas – going from CO2 (gas) to CO2 (liquid) to solid carbon requires energy.

    That sounds about right.

    I found:

    According to the EIA, emissions per ton of coal range from 1.40 tons of CO2 to 2.84 tons of CO2, depending on the type of coal (1.40 for lignite, 1.86 for subbituminous, 2.47 for bituminous, and 2.84 for anthracite, to be precise),[19] so a tax of $100 per ton of CO2 translates to a tax of between $140 and $284 per ton of coal, depending on the type ($140 for lignite, $186 for subbituminous, $247 for bituminous, and $284 for anthracite).

    Carbon tax

    … which refers to:

    Voluntary Reporting of Greenhouse Gases Program (Fuel and Energy Source Codes and Emission Coefficients)
    Energy Information Administration

    Additionally, even when you capture carbon dioxide there is the issue of sequestration:

    The mineral carbonation process would require 1.6 to 3.7 tonnes of silicates per tonne of CO2 to be mined, and produce 2.6 to 4.7 tonnes of materials to be disposed per tonne of CO2 stored as carbonates. This would therefore be a large operation, with an environmental impact similar to that of current large-scale surface mining operations.

    IPCC Special Report (see above), pg 37

    You might also look at:

    Carbon Capture and Storage

    … but this time be sure to check the primary texts, that is, the sources.

    In any case, it is worthwhile pointing out that while the costs of renewable energies should come down with economies of scale and R&D, in the long-run the costs of limited fossil fuels can only increase with time, particularly as we go from the most accessible, high grade deposits to less accessible, low grade deposits. And to the extent that we invest in the fossil fuel infrastructure needed to replace conventional oil, we will be locking ourselves into the use of fossil fuel rather than investing in the future. Furthermore, currently all we have from industry is little more than a promise that they will use CCS as it becomes economically feasible to do so.
    Captcha fortune cookie: 20 diapers

    Not much carbon capture there, I’m afraid.

  50. 150
    David B. Benson says:

    Ike Solem (147) — France has a modest amount of pumped hydro, usueful for load balancing.