U.S. Energy Secretary Steven Chu’s off-beat idea of painting roofs white all across America is an initiative he has been promoting eagerly, the Voice of AmericaNews.com reported Sept. 21. Now he wants white roofs all over the world. That won’t be easy in countries with thatched roofs. Chu is President Obama’s Nobel prize-winning green guru. So, what’s with the white fetish?
A coat of white paint on a roof can lower both carbon emissions and cost, Chu has contended. The concept he espouses is this: as sunlight beams down on us, roughly half the energy shines as light. The light heats our rooftops. If the roof is white, the sunlight will reflect off the roof instead of heating the roof’s surface. By reducing the need for energy that cools our homes and offices, tons of carbon dioxide (CO2) emissions could be saved, slowing global warming.
Chu won the Nobel in 1997 with two other scientists for devising methods to trap atoms with lasers. He’s certainly no climatologist. No matter, apparently, that increasing numbers of respected scientists have doubts about global warming. In fact, many eminent scientists now claim the world has entered a “cold mode” which is likely to bring a dip in global temperatures that will last 20 to 30 years, the Daily Mail of London reported in January. Some politicians, but few scientists, still believe in the catastrophic forecasts that helped Al Gore acquire hundreds of millions of dollars with his fright tactics.
There’s no reason to restrict cool roofs only in America, in Chu’s thinking. At a Nobel laureate symposium in London, he suggested that the world’s roofs should all be painted white as part of the effort to control the climate. He described climate change as a “crisis situation,” calling also for “wind, wave and solar” to supply energy for the globe. His own Energy Department has compiled statistics showing the lack of promise for such renewable energy sources at any time in the calculable future.
The Sunday London Times also reported that Chu said building regulations “should insist that all flat roofs [be] painted white,” and visible tilted roofs could be painted with “cool-colored” paints which absorbed much less heat than conventional dark surfaces. He also recommended that roads could be lightened to a concrete color so they would not dazzle drivers in bright sunlight. “I think with flat-type roofs…yes, I think you should regulate.” Spoken like a true-blue patron of bureaucratic control.
In his passion for cool roofs on government buildings, Secretary Chu directed all Energy Department offices to install white roofs during new construction, when replacing old roofs and whenever an installation is cost-effective over the lifetime of the roof, The New York Times reported in January. In a news release July 19 he urged other federal agencies to follow suit. The Energy Department (DOE) has 10,500 buildings. The Federal government owns or leases 500,000 buildings. That’s a lot of white paint.
You say "increasing numbers of respected scientists have doubts about global warming". A statement like this really deserves some real evidence otherwise you lack any credibility. Of course you and I know you cannot substantiate it as the science around global warming is getting more certain not less.
Douche-Bag…Look at the Long timeline of weather patterns. Look as recently as the "Dark Ages". It was an extended period of slightly cooler weather, across most of the northern hemispher, encompassing Russia, Germany, France, England, etc, etc. The earth goes in cycles of fairly warm, slightly cool, back/forth, so-on, and so-on.
What do you think, the Dinosaurs had Gas/Diesel engines and burned tons of coal and that was the fuel to their demise? It is just a natural process that the earth goes through.
I will say that it is very likely and probably true that humans have sped up the process, mainly since the Industrial Revolution. BUT…however, Humans did not cause this to happen just by ourselves…we contributed and made the process faster. I do still plan on driving my Silverado as much as I can tonight after work, just so you lose sleep at night for the next week.
Antony,
Requiring REAL EVIDENCE from this author requires YOU reciprocate in kind with REAL EVIDENCE of the science around global warming, now changed to an new and improved title to global temperature disruption, is getting MORE CERTAIN, not less.
PROVE IT!
You write "many eminent scientists now claim the world has entered a “cold mode” which is likely to bring a dip in global temperatures that will last 20 to 30 years, the Daily Mail of London reported in January." – http://tiny.cc/4c430
The many scientists you refer to is a scientist called Mojib Latif and he was totally misquoted in the above article. This is his response to the Daily Mail article – "It comes as a surprise to me that people would try to use my statements to try to dispute the nature of global warming. I believe in manmade global warming. I have said that if my name was not Mojib Latif it would be global warming." … "There is no doubt within the scientific community that we are affecting the climate, that the climate is changing and responding to our emissions of greenhouse gases." – http://tiny.cc/c5dl6
He is saying that he BELIVES in global warming.A lot of scientist believe in ulcer being desease of behavior rather than infection. Believe is not a science. There are no deffinitive proof of man made changes. Earth is not fixed planet it continoues to evolve and so is climate.
There is definitive proof. Scientists have tracked the CO2 levels since the industrial revolution, bostonian. You will see there is a definitive correlation between human's actions and the rising CO2 levels. It's science, and it's not debatable. And please don't say CO2 levels don't matter–if you really think that's true, go to your garage, start the car, leave all the doors and windows shut and enjoy all the CO2 you can handle…until you die. CO2 matters, and it's humans who are creating the increased levels.
You are confused as most liberals are. The exhaust that your vehicle emits is
CO, a poisonous gas. The human body and some industry emits CO2. Yes let's get rid of all CO2, there is too much plant life in this world anyway.
CO=carbon monoxide; inhalation is incompatible with life as it prevents oxygen molecules from adhering to hemoglobin and causes suffication and death.
CO2=carbon dioxide; the normal by product of respiration and a requirement for plant life to exist. Plants absorb CO2 and release oxygen for our respiration.I gave a simplistic definition for this demo.
Antony,
This is all you have to offer? Wow! Maybe you should be a writer, since you have no idea what you're talking about, you will fit right in.
FREE hot water from solar heaters is the NORM in countries like ISRAEL and I don't believe they cost the fortune those few mfrs in good old USA pretend to charge us for it.
There is one way of saving electricity galore and certainly, that of painting roofs white
could contribute to lower SOMEHOW the cooling load of our houses, not that of our apartment buildings
Anybody check to see if Chu's roof at home is white? I bet it isnt.
Chu is trying to lead us to paint our roofs white. The best way to lead is by example. All those who believe in global warming, from the President on down, should set an example for us by painting white the rooftops of their personal homes. (Not our White House). And, this should be done with their own money, not that of taxpayers. When they complete painting their own homes, I will do the same!!! You feller write when when you get 'er done!
If I paint the roof of my house white, then I won't be able to install solar cells to substitute a few kW-Hr of solar electricity for electricity generated by burning coal. Did Steven Chu think about this?
The issue is not painting your house in the suburb's roof white, it is installing white roofs on Government, commercial, medical, apartment and industrial buildings most of which are located in cities where they along with their parking lots add to the urban heat island effect raising temperatures from 7 to 10 degrees F compared to their outskirts. Try getting out of your house once in a while and take a look at what percentage of the World's people live between 40 degrees North and 40 degrees South latitude and in cities and you will see that cool roofs make a lot of sense for a lot of buildings. And tell Rob down below that the latest version of LEED is weighted for those points which make the most sense in your climate zone.
"then I won't be able to install solar cells"
Why is that?
In Arizona, if you paint your roof white and you decide later to sell your home, you will have to replace your roof — this is rule many lenders follow. Why? Some people apparently paint their roofs white to cover any broken or torn shingles which may have caused water damage in the roofs substructure. A white coated roof does not let the inspector inspect for damage as it covers it — I guess.
I thought, when all the roofs in my neighborhood were being painted white that it was a great idea, but was too lazy to do it myself and didn't want to pay the $2,500 price tag for someone else to do it. Boy, was I glad when I learned that several neighbors had to replace their roof before FHA would provide a loan to a prospective buyer because of the white roof. One neighbor had to replace his two-year old roof with a new one — SO, MORAL OF STORY — CHECK LOCAL LAWS AND CALL LENDERS TO SEE IF THEY WILL WRITE LOANS ON HOUSES WHOSE ROOFS HAVE BEEN PAINTED WHITE. If they won't then ignore this idiot!
so allowing your house not to gain heat in the summer sounds great, what does that do for those who live up north in the winter, burn more fossil fuels. someone needs to explain the conservation of energy laws to these idiot physicists.
I totally agreed. White roofs may be okay for California, Arizona, Florida and other southern States but are a waste of time and money for States that see cold weather. I imagine the intial reflectivity is significantly diminished when the white surface becomes dirty.
Secondly I don't want the government telling me what kind of roofing membrane or coating I should use. I want my choice of a roofing sytem to be based on what I feel is required and performance is high on the list.
Howie and Leif…I agree with you both. I currently live in Ak and previously in VT and Northern, NORTHERN, NY State. It is Butt Cold in the winter up there. The dark black roofs contribute to warming my house in the winter. I guess if the Government mandates the color of the roof of your home, then Obama is one step closer to his ever so desired Socialism. I guess the next step after making us all paint our roofs white would be to apologize to the rest of the world, and mainly the mideast, about Bush not doing this earlier.
Have a good weekend!!!
In my house in WY, have a crappy old AC. On hot days, my constantly working AC could not lower the temperature below 85. Then I sprayed-painted my roof. It's not really white, just kinda whitish. I don't have the overheating problem anymore. It took me just a couple of gallons of paint. In Northern states, the sun does not really warm the house through the rood during winter, but it sure heats it up during summer.
Chu has good intentions but he's misguided by the environmentalists. Cool roofs save the building owner $$ on electricity used for cooling, especially during peak demand. That should be the message which is factual and easily demonstrated. The global climate statements and issues are well..suspect at best.
Chu's right about white reflecting light and heat. That's been common knowledge in desert and Mediteranean climates for thousands of years. It's ironic that I'm in the process of sealing my mostly flat roof, and the two main products sold are either silver or white, for those very reasons. So it's logical in warmer climates like the sun belt. The bad news is that there is a national shortage of white paint. We don't even have enought to paint stripes on roadways, so Chu is not totally in touch with other governmental needs. http://www.countyenews.com/index.php?option=com_c…
As for global warming, the man to read is Lester Brown, not Al Gore. http://www.earth-policy.org/images/uploads/book_f…
And for some very scary stuff for the SW U.S. check this out. http://www.circleofblue.org/waternews/2010/world/…
Calculate the solar gain you get in winter and the solar heaaat you can reflect away when the sun is higher and the day is longer, it is not even a contest. The solar gain on a northern roof in winter is negligible while the savings from reflecting the summer sun are real.
I wish these 'educated' people would take the time to look at the data that already exists out there, do the math, and really qualify thier output… it is this type of broad-based hysteria that they put out that causes the broad-based hysteria in our industry…
Amazing. Are buildings that are in climates where there are more heating degree days than cooling degree days supposed to coat their roof white, and require more energy to heat the building? How about adding insulation to offset heat gain in summer and reduce energy requirement in winter?
Paul, I think you want the insulation to keep the heat in the building in the winter. In the summer, you want the roof to stay cool so that you aren't wrapping your home/office in a ~170 degree blanket and then trying to cool it. Note that the delta T is actually much higher in the summer than winter once you realize that the roof is close to 100 degrees warmer than the desired indoor temperature (since the attic is seeing that 170 degree temperature, not the outside air temperature). Comparatively, the delta T for winter is rarely anywhere near that high, or, in any case, not nearly so high for nearly so many hours.
Above the 49th paralell on the west coast we are only turning on the AC for 2 weeks in the summer at best. most of the year we are heating and would be better to absorb what sun there is. A blanket statement about white roofs for a LEED point has buildings in northern BC and the Yukon adopting the craze. Extra insulation and smaller windows are the keys to saving energy. White loose clothing and a broad rimmed hat when outdoors could keep people from turning the AC up. What percentage of the earths surface is covered by roofs?
When I became a roofing contractor 30 years ago I was told that a black roof would only add about three degrees to your roof it were properly ventilated. We didn't know how to ventilate back then anyway. We just vented pressure and did not cause a 'Chimney Effect" wind.
I know that heat goes where heat isn't and white roofs get really hot. Under the granules is black asphalt. Believe me the heat is absorbed on white comp roofs.
flat roofs with elastomerics or white membranes make much more difference because there is no black asphalt to conduct the heat to.
Only the reduction of the absorption and reflection back into space will keep the atmosphere from being warmed.
White comp roofs don't do much.
Mr. Chu and Itis Fitz above are absolutely right on man-made climate change and the lack of significant heat gain on roof surfaces in the winter. A lot is being made of white paint in these comments, as an Architect involved in energy modeling and roof design of buildings I have used a number of approaches to increase the reflectance of roof surfaces. There are white membranes made of EPDM with a coating, TPO (naturally white) and PVC (can be made in white, light gray, or tan) and an asphalt roof can be coated with aluminized paint which increases reflectance and protects the asphalt from UV radiation. I have never used white paint. Flat roof membranes are generally replaced every 20 years so there are enough opportunities to replace existing dark roofs with white roofs to make a very serious impact on cooling energy use in the next 20 years.
Spare me the histronics of Gorebull warming versus white roofs. It makes no difference if your roof is white, black or pink if your building is properly insulated. Insulation keeps heat, as well as, cool, inside the building. If you want to talk about efficiency, fine but, don't try to make out that painting your roof white will have an effect on the climate. As for the Kool-Aid drinkers that have lent their boozy voices here, particularly the fellow who thinks you die of CO2 poisoning if you leave your car running in a closed garage then enter, please tell me again why a warmer earth is bad. Increased CO2, even in the miniscule increases supposedly recorded, is good for plants and plants, let me use crops here, growing all the way to the Arctic circle would be a boon to the world's hungry, not to mention all the land opened to actual living without 50 pounds of clothing year round. Kind of like in the Medieval Warm Period. How is that a bad thing?
Smack them again Sniper! Though I think Stinky Crow did allow three squares and you must install a bidet. Hmmm (yes I'm a copycat) that would mean more water too and I thought water was our next big crisis. I simply don't know how we made it this far without progressives to lead us out of our ignorance. Actually, the solution is to let the earth warm up, encourage it, in fact. Then more trees would grow faster and farther north and we would have enough for toilet paper which would save water. I'm on a roll here. Maybe I could be one of The One's czars? How does one apply? Oh, I forgot, I don't have a Nobel or go to Harvard.
White roofs to slow down climate change? I don't care if this guy is a Nobel Prize winner,this sounds extremely stupid to me. Does it seem stupid to anyone else?
Yes, this Nobel Prize winner sounds stupid because a physicist does not a climatologist make. Apparently Obama thinks anyone who is a scientist should be allowed to weigh in on areas where they lack knowledge or actual experience. Just like doctors, scientists have specialized themselves out of being generalist in science. They know their field and only their field, and rather than seeing how that might apply to another field, they keep, say physics separate from climatology, for fear of losing control over their ONE and SINGULAR little piece of nerdiness.
Sweetie, when winter comes, Mother Nature "paints" our roofs white. We like to have black ones, in Cleveland, OH – absorbs more heat, which we need about then.
The slant of the roof is what counts. A man I know found plans for a house in Popular Mechanics that was said to be heat and cool efficient. Most of the flat area was to the north. That included the roof. On the south side was a full length porch that reached up 2/3 . But under the porch was a deep wide square hole. That part of the porch only had beams and no floor. The rest of the porch had a floor. He was right he never needed an air conditioner.
This was Las Vegas so the winter was no problem.
Unfortunately years later his kids became dope addicts and his wife divorced him. So I guess heat efficient houses do not solve all problems.
Hahahahahaha good one Jim!
Typical academic…white rood technology considers neither the extraordinary high cost associated with cleaning the roof nor the radical drop off in efficiency when it is not cleaned.
Another Nobel Prize winner? Considering that Obama won the prize due to his potential, who knows whether Chu's is deserved. Environmentalism gone wacko. Then again, is Global Warming caused by rising CO2 levels? I understand the ice caps on Mars are melting. Global warming on Mars? Maybe its the Sun! 2 +2 = 11. That's what we are suppose to believe because government says its so. All these energy regulations, Cap & Trade is a scheme to redistribute weallth and increase executive power. Mr. Chu, might I suggest painting the top of your head white and wearing nothing but white suits.
Oh, my achin arse!! There's just no end to the bafoonery of these people. Just when you think you've heard it all, one of these twits comes up with something else. White paint huh?? First off, you twits outlawed oil base paint in New York State. God knows we were destroying the environment with oil base paint. PS. I know that they actually mean roof coating and not paint.
Chu's own Dep't of Energy has a tool called the "Cool Roof Calculator" that shows (with real data) that a dark-colored roof reduces energy costs and consumption as well as carbon emissions in cooler climates, yet he still continues to spout off about reflective roofs. I think he better figure out what's going on in his own Dep't. before he tries to tell the world what type of roof they should install.