JoNova

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If we paint all our cities white, will we get more snow?

Some bright spark has found a way to make white paint extra reflective which will reduce cooling costs (but presumably increase heating costs in winter). In theory, this will cool the world, stop storms and save turtles.

Once, when we were rich we could afford to have colors on our buildings and to heat or cool them too.

Presumably this will also be good for the sunglass industry. Let’s hope it doesn’t cause more car accidents.

Climate change: ‘Cooling paint’ could cut emissions from buildings

Matt McGrath, BBC

A  new type of white paint has the potential to cool buildings and reduce the reliance on air conditioning, say researchers.

In a study, the new product was able to reflect 95.5% of sunlight and reduce temperatures by 1.7C compared to the ambient air conditions.

The engineers involved say the impact is achieved by adding different-sized particles of calcium carbonate.

Here’s wondering when the next study shows that a bunch of skyscrapers reflected white light away from themselves and towards other skyscapers, raising their cooling costs.

 

 

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Rating: 9.8/10 (40 votes cast)
If we paint all our cities white, will we get more snow?, 9.8 out of 10 based on 40 ratings

47 comments to If we paint all our cities white, will we get more snow?

  • #
    TdeF

    “Say researchers”, “scientists say” and in this case “the engineers involved”. This is advertising presented as news, or a search for funding presented as a breakthrough idea worthy of investigation. Fake Green science.

    Everything these days has to save the planet, this one by doing something of really dubious value. Green carpetbaggers. Big buildings have a major problem getting rid of heat anyway, even body heat and even in winter. The argument here is that the cooling required will be reduced if incident sunlight is reflected rather than absorbed, but it first has to be proven that it is a major reason cooling is needed.

    If you want publicity and funding, you only have to say that you will reduce ‘emissions’ which is Green code for the poisonous, deadly chemical CO2. The world has gone mad when the press tell us daily, directly or indirectly, that carbon dioxide is the greatest threat to human existence when in fact it is the only reason for human existence.

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  • #

    How about painting the grey pole and mounting frame underneath our Stevenson screens with it. If this reduces the temperature of the air rising off the pole up into the box through the deliberate gaps in the floor slats then it could save the whole country a lot of heating and cooling costs.
    A 1.7 degree drop in Australian area averaged temperatures might be too much to hope for.
    https://commons.wikimedia.org/wiki/File:Interior_of_a_stevenson_screen_at_the_Darwin_Met_Office.jpg

    70

    • #

      Siliggy, how dare you. As if the BOM cares less about removing artificial sources of warming…

      Don’t give them ideas on painting those poles black.

      51

  • #
    Graeme No.3

    Amazing new technology! Well almost. 25 years ago the company I worked for trialled an ‘insulating paint’ on a tank getting a lot of sunlight (from sunrise onwards) and it worked. So much so that they repainted the other tank used as the ‘control’. So if the (water containing) tank was cooler then obviously the paint was reflecting heat.
    And it didn’t require “different-sized particles of calcium carbonate”.

    50

    • #
      Graeme No.3

      Pressed the POST not PREVIEW (need coffee).

      The extra calcium carbonate just raises the PVC above the CPVC point, i.e. there is an increasing amount of air filled (micro) voids in the paint. They reflect light (opacity much higher) but there are side effects like staining, reduced water resistance and shorter life of the coating.

      Critical Pigment Volume Concentration (CPVC)
      As the ratio of binder to pigment changes, one reaches a sweet spot where the pigment is at its maximum loading while still having all the air between the particles completely filled with binder. This optimal point is known as the Critical Pigment Volume Concentration, or CPVC. While every paint system will be different, the CPVC generally falls somewhere in the 30-60% range. As one moves along this continuum (Image 2), and past the CPVC, one moves towards a paint film that has an increasingly large number of voids, which in turn leads to a layer that is more matte, more permeable, and increasingly fragile.
      From https://www.justpaint.org/pigment-volume-concentration-and-its-role-in-color/

      81

      • #
        sophocles

        Wow — all these tekkernikkle discoveries!
        So that’s how the Romans dun it!

        Isn’t life wonderful: if it wasn’t for the CGs (Crazy Greens), we would never know or even find out all this oh-so-wonderful trivia …

        But life created Crazy Greens so we get their Treatises …
        (Where’s my current book? It’s more interesting … Graeme Hancock’s “America Before” …)

        As for the Ice Hockey Team: issue them with a jar of Cholecalcifidiol tablets (take 4 – 8 per day depending on how fragile you feel …) and write your last W & T …

        (W & T = Will & Testament.)

        00

    • #

      Legend has it that Archimedes was defeated by the Romans who used this paint on their ships.

      40

    • #
      Ted O'Brien.

      Outdoors in summer sun, you will find that raw aluminium does not get hot, most white paint does not get hot, polished stainless steel does get hot, and just about anything else too. I imagine there are a lot of different white paints, and some of them might do strange things.

      The heat conductivity of whatever it is makes a very big difference to the feel of it, too. e.g. metal feels hotter (or colder) than wood.

      00

      • #
        yarpos

        yep, massive grandstands of aluminium seating in full summer sun quite comfy at least from a temp perspective

        10

  • #
    tom0mason

    “If we paint all our cities white, will we get more snow?”

    Well yes of course however it will show-up the unicorn excrement better. [/sarc-off]

    More offers of a fix for a non-problem!

    20

  • #

    If we apply enough white paint to our cities, we not need to have any more snow at all as the effect will be exactly the same. Then we can start on the countryside and do away with snow altogether. After that we can more on to tackle some real and pressing matters.

    30

  • #
    Harves

    Let’s paint the world. Yaaay, problem solved.
    Funny how all those enlightened Hollywood alarmists all drive around in black limos. Some would say they are hypocrites?

    40

  • #
    Curious George

    Isn’t this a racist proposal?

    51

  • #
    Ken Stewart

    “adding different-sized particles of calcium carbonate.”
    Oh no! That dreaded carbon is everywhere!

    60

    • #
      tom0mason

      Ken Stewart,

      Yes and how do you keep those particles at the correct size.
      Calcium carbonate does not react with CO2 under dry conditions.
      However if water is present the solid calcium carbonate reacts and dissolves in the water, according to the overall reaction —
      CaCO3 + CO2 + H2O —>(Ca+2)+(2HCO-3) [where the +2 and -3 indicate the ionic products.]
      This is the process that forms those caves, stalactite, and stalagmites in limestone deposits.

      30

      • #
        sophocles

        and uses up great quantities of CO2.

        It’s what has brought atmospheric CO2 down from 4500 ppmv (250MYA) to a mere 415ppmv.

        30

        • #
          Ted O'Brien.

          While you are on that subject,

          I know, and presume that you know, that all of the fossil carbon in all the coal, shale and petroleum in the world was at least once in the atmosphere.

          How much of the other “fossil” carbon was once in the atmosphere? Such as graphite, limestone &c?

          00

  • #

    Nothing new. Cenospheres, hollow ceramic microspheres, have been around for ages. Used on spacecraft etc. The paint helps if applied to shipping containers used for dwellings; up here it helps to protect the contents from being cooked. Cenospheres are a by-product of burning coal (shockhorror) and the hollow is mostly carbon dioxide (moreshockhorror). Roofs and walls here are mostly painted or coated white (or at least Colorbond surfmist) because there is a significant gain with respect to complying with the NCC (National Construction Code). Doesn’t please everybody. On several occasions as a regulator I had to address complaints from fat-cats who live up the hill that they were being dazzled by the reflection off the roofs of the rest-of-us who live down the hill. Quite a challenge, as I was required to be polite …

    50

    • #
      Graeme No.3

      Martin,
      quite right. There are other approaches based on air or gas bubbles sealed within the paint film, but the choice of calcium carbonate was a real giveaway. They formulated above the CPVC. Yes, the paint would look dazzling white — for a while. I am thinking of the ‘entrepreneurial’ types who left a paint company in Melbourne with a plan (and a formula). They changed the formula a bit – more (cheap) calcium carbonate filler, less (expensive) resin and got 3 “show houses” painted a dazzling white on a main road, along with a large advert. 3 weeks later it rained – it does in Melbourne – and a deal of the paint washed off.

      Re IR reflectant paint, I guess you have decided that the IR reflective pigments (dullish greens mainly) by Shepherd etc. are too expensive. Suggesting a repaint (at their expense) by the fat cats wth a costing would probably shut them up.

      20

  • #
    graham dunton

    These insulating coatings have been around for a long time, one I was interested in, is manufactured in WA, they do not have to be white, although white is more reflective, it becomes dirty very quickly.
    The WA product comes in many colors, I was considering it for the re- coating of old concrete roof tiles, which have become very porous, which in turn increases the roof loading considerably during the wet season.

    40

    • #
      Graeme No.3

      graham; seal the roof first. Martin Clark #9 might be interested.

      20

    • #
      Lucky

      Quite so. One manufacturer is Insultec.
      I used this product about 30 years ago. I think it worked and yes it gets dirty, cannot get a smooth high gloss finish.
      Read the test reports carefully, it does work, so if you want a dark color roof go with this product. But better, go for a white color which reflects heat and light more than other colors. With white the reflecting paint has marginal benefit if any.

      00

  • #

    Dear Joanne,

    The concept of ‘nanotechnology’, adding reflective particles to paint or pottery clay to either reflect or diffuse light, is as old as the Romans. I know of large shopping-centres whose rooves have been treated with nano-paint to reflect sunlight in order to reduce heat load and make their air-conditioning systems more efficient and use less energy.

    I used it myself (normal white-coloured paint) on top of a concrete roof of my office circa 1990 – it worked. I had two window-mounted air-conditioning units on one side of the office plus (most importantly) an air-exhaust fan on the other side.

    The white paint reflected about 40% of the heat, the exhaust fan improved the flow through ventilation of cooling air which lowered the heat load on the air-conditioning units and reduced energy costs. In 1990, it was called ‘passive solar resistance’ and recommend for houses and dwellings by the CSIRO Building Station – there is quite a bit of literature about it – I suggest that you look it up.

    30

  • #
    Salome

    Given the dominance of glass on the external surfaces of skyscrapers, there’s not much left to paint.

    60

  • #
    Graham Richards

    It’s not the loons & crazies I worry about, it’s the dumbass politicians & general members of society that will actually believe every word of it without asking a single question.
    I really fear for the future.

    40

    • #
      Serp

      This is the future; when lockdown was declared and people’s livelihoods and educations and justice systems were summarily amputated it was omitted to mention we’re to forget the past.

      10

  • #

    Typical, it’s always gotta be white.

    Black Paint Matters!

    Tony.

    121

  • #
    sophocles

    Don’t you use that in Winter, Tony?

    20

  • #

    Jo
    Many years ago an engineer I used to play squash with expressed concern over the proliferation of the reflecting skyscrapers on the heat being reflected into other buildings and pushing up their cooling costs. This will do likewise in crowded areas.

    41

  • #
    MichaelinBrisbane

    Might as well paint all the solar panel white, too, for all the good they do.

    71

  • #
    pattoh

    “adding different-sized particles of calcium carbonate”

    As I recall, there was quite a to do when lime washing was replaced by acrylic for painting Stevenson Screens.
    Laughable that 19th century technology may prove yet to be better to fight “Thermometer Driven” Climate Change.

    Pity there was little or no discussion on the “thermal collector/ re-radiator” steel posts thay are all mounted on these days.

    10

  • #
    Saighdear

    … and then there are White sheep & Black sheep, white cows and black cows, Pink naked hairy piggies, and around the Arctic circle, you can find WHITE bears and Dark coloured bears. … so much for Evolution to cope with the environment.. You can think for yourselves about mankind …..

    00

  • #
    BruceC

    (but presumably increase heating costs in winter)

    Yes, I could see that as a little problem;

    In one experiment where we put a painted surface outside under direct sunlight, the surface cooled 1.7C below the ambient temperature and during night time it even cooled up to 10C below the ambient temperature

    10

  • #
    DonK31

    Regarding the headline: No. There will not be more snow. But it will look like it. Kinda like a Potemkin Village.

    00

  • #
    CHRIS

    Getting painted into a corner, just like the idiotic ideas these morons come up with (duhhh)

    00

  • #
    Reed Coray

    Buildings require the use of fossil fuels to maintain interior temperatures compatible with human use. According to AGW theory, fossil fuel use by humans is bad because it increases atmospheric CO2 levels, which according to the theory, causes global-warming/climate-change/climate-disruption, or whatever phrase will scare the bejesus out of the general public. The professed goal of applying highly reflective paint to buildings is to reduce the amount of fossil fuels needed to provide interior building temperatures suitable for human use. For surrounding environments that are colder than desired by humans, this means using fossil fuels to heat building interiors; and for surrounding environments that are warmer than desired by humans, this means using fossil fuels to cool building interiors. Bottom line, as far as buildings go, fossil fuels are used to maintain a temperature compatible with human occupation; and the issue to be considered is: “Will painting buildings with a highly-reflective paint reduce fossil fuel use; and if so, is that reduction worth the cost, effort, and intangible negative effects of painting the buildings?”

    [Note: Because the orientation of an object in direct sunlight has an effect on the object's temperature, weather service reported temperatures represent the temperature of objects in the shade. Thus, by "surrounding environment temperature" I mean the temperature of nearby objects in the shade (not those in direct sunlight). If you don't believe an object's orientation in sunlight can effect it's temperature, try the following. At noon on a hot day take two identical metal crowbars and stick them in the ground in direct sunlight with one crowbar oriented parallel to the incoming solar radiation and the other crowbar oriented perpendicular to the incoming solar radiation. Go to lunch. After returning from lunch, pick up both crowbars with your bare hands and decide which one you'll use. So for this discussion, ambient background temperature (or ambient surrounding temperature) is temperature in the shade--i.e., not in direct sunlight.]

    Okay, let’s analyze the goal of reflective paint fossil fuel reduction for four conditions: (1) ambient surrounding temperature greater than desired, incoming solar radiation present (daytime, cloudless); (2) ambient surrounding temperature less than desired, incoming solar radiation present (daytime, cloudless); (3) ambient surrounding temperature greater than desired, incoming solar radiation absent (nighttime or cloudy); (4) ambient surrounding temperature less than desired, incoming solar radiation absent (nighttime or cloudy).

    Condition 1: Ambient surrounding temperature greater than desired, incoming solar radiation present (daytime, cloudless)–fossil fuels are used to cool the building. For this case, a highly reflective paint will likely reduce fossil fuel use. The incoming solar radiation will likely increase the building’s internal temperature above the ambient surrounding temperature because the building will absorb some of the incoming solar radiation. Painting the building with a highly reflective paint will reduce the amount of absorbed incoming solar radiation, and therefore require less fossil-fuel cooling. On the other hand, the highly reflective paint will reduce the rate energy is radiated away from the building–not reflected from the building, but removed by radiation from its interior; and to compensate for this reduced cooling effect, additional fossil fuels will have to be used. But everyday experience tells me that all else being equal (no change in conductive or convective heat flow), for Condition 1 a highly reflective surface will require the use of less fossil fuel.

    Condition 2: Ambient surrounding temperature less than desired, incoming solar radiation present (daytime, cloudless)–fossil fuels are used to heat the building. For this case, a highly reflective paint will likely increase fossil fuel use. Absorbing, not reflecting, incoming solar radiation will increase the building’s internal temperature–the desired goal. Covering the building with a highly reflective paint will decrease the amount of absorbed incoming solar radiation, and to make up for this loss of heat, additional fossil fuel will be needed. On the other hand, the highly reflective paint will reduce the rate energy is radiated away from the building–not reflected from the building, but removed by radiation from the building’s interior, which will reduce the amount of fossil fuel needed to overcome interior heat loss via radiation. But again, everyday experience tells me that all else being equal (no change in conductive or convective heat flow), for Condition 2 a highly reflective surface will require the use of more fossil fuel.

    Condition 3: Ambient surrounding temperature greater than desired, incoming solar radiation absent (nighttime or cloudy)–fossil fuels are used to cool the building. For this case, a highly reflective paint will likely increase fossil fuel use because whether or not the building is covered with highly reflective paint, little if any incoming solar radiation will be absorbed by the building’s–so covering the building with a highly reflective paint will have little effect on the rate of solar heat capture. However, covering the building with a highly reflective paint will reduce the rate energy is radiated away from the building. Since in Case 3 the goal is to remove heat from the building, additional fossil fuels will have to be used to compensate for the reduced radiative heat loss.

    Condition 4: Ambient surrounding temperature less than desired, incoming solar radiation absent (nighttime or cloudy)–fossil fuels are used to heat the building. For this case, a highly reflective paint will likely reduce fossil fuel use because whether or not the building is covered with highly reflective paint, little if any incoming solar radiation will be absorbed by the building’s–so covering the building with a highly reflective paint will have little effect on the rate of solar heat capture. However, covering the building with a highly reflective paint will reduce the rate energy is radiated away from the building. Since in Case 4 the goal is to prevent heat from leaving the building, the reduced radiative heat loss will result in less fossil fuels being needed.

    Based on the above, in two of the four cases covering buildings with highly reflective paint will reduce fossil fuel use and in two of the four cases covering buildings with highly reflective paint will increase fossil fuel use. To determine which effect(s) dominates would require a complex analysis of ambient background temperatures, solar orientation in regions with significant buildings, cloudy/cloudless days, where does the reflected solar energy go (to space or to the earth), etc. But even before that analysis, the questions would have to be asked/answered: “If we covered every building with a highly reflective paint, (a) would the net change in energy (absorbed solar and that generated by fossil fuel use for the purpose of building heating/cooling) be measurable, (b) if yes, is the net energy change meaningful, (c) if yes, is it beneficial or detrimental, and (d) if beneficial, do the detrimental side effects, if any, outweigh those benefits? When I drive across the western United States and see just how much area is devoid of buildings, I’m bewildered by the idea that changing the reflective properties of every building on the face of the earth will have any measurable effect on the earth’s temperature whether or not those buildings are maintained at a temperature compatible with human use.

    I’m pretty sure what my answers to the above questions would be if I manufactured or sold highly reflective paint. I’m also pretty sure what my answers would be if I was routinely blinded while driving to and from work by sunlight reflected off buildings. I can guess what my answers would be if I were a liberal who believed in CO2-based AGW; or if I were a conservative who didn’t believe in CO2-based AGW. I’ll let anyone who reads my comments and gives a hoot to guess what my answers actually are.

    20

  • #
    Rosco

    So now we’ll have the white house effect with whitehouse gases – imagine the potential for uni subsidized research.

    10

  • #
    Doonhamer

    Solar reflective paint.
    Military have known about this for decades.
    And it does not have to be white.
    Can you think why they do not want their great lumps of metal getting warm?
    And it is not just for the comfort of the Diggers.

    10