Los Angeles tests cooling pavement paint to beat heat

Posted: August 14, 2017 by oldbrew in innovation, News, Temperature
Tags: ,

LA street [image credit: theatlantic.com]

Whether this is anything more than a gimmick remains to be seen. It’s described as an experiment ‘to reduce the heat island effect’.

Can a splash of gray pavement paint help combat global warming?

In Los Angeles, where summer temperatures regularly surpass 100 degrees Fahrenheit (38 degrees Celsius), workers are coating streets in special gray treatments in a bid to do just that, as Phys.org reports.

The City of Angels, home to four million people, is the first major city to test the technology. Normal black asphalt absorbs 80 to 95 percent of sunlight, while the gray “cool pavement” reflects it—dramatically lowering ground temperature and reducing urban street heat, advocates of the method say.

During a demonstration of the technique, Jeff Luzar—sales director at GuardTop, which markets the product—showed how applying the paint could drop street temperatures by about 12 degrees Fahrenheit after just one coat.

Los Angeles is the first city in California to test the treatment on a public road, after initial trials on parking lots, according to Greg Spotts, assistant director of the city’s Bureau of Street Services. “We’re hoping to inspire other cities to experiment with different ways to reduce the heat island effect,” he said. “And we’re hoping to get manufacturers to come up with some new products.”

“Potentially there could be a huge market for cool pavement products, and in fact, it’s part of a much larger economic trend where solutions for climate change could be the next great investments for the future,” Spotts added.

The city will also monitor how Angelenos react to the newfangled asphalt—and how quickly the notoriously thick LA traffic dirties the gray coating.

Continued here.

– – –
See also – US EPA: Heat Island Cooling Strategies

  1. oldbrew says:

    In the US, pavement = road surface.

    ‘In the UK, a pavement is the hard raised level surface at the side of a road that people can walk on: I set it down on the pavement by the door of the shop. American speakers call this a sidewalk. In the US, pavement means the hard surface of a road: Cars were skidding on the pavement.’


    There are nearly 8 million registered vehicles in LA county.

  2. Jim says:

    To me it is unnecessary. A waste of taxpayers monies. I will explain. After three or four years, asphalt has aged. It turns a light grey. Cities, then overcoat the light grey with a ew coat of black by ripping off the old and mixing it with new oil, and respread it as a new street. So, now all they should have to do is fill in the weather checking and the potholes? Both faster and more cost efficient then repaving.

  3. Tim. says:

    Perhaps the UK could paint our roads black to raise the temperature a bit.

  4. spetzer86 says:

    I wonder about the longevity of the paint on heavily traveled roads? Of course, if it required annual “touch-up” coverings, it’d be an “other people’s” money maker all around.

  5. Hifast says:

    Los Angeles streets are already renown for their lack of traction (oil dripped from vehicles) during the first autumn rains. Painting the streets? Let’s see how this works.

  6. peterandnen says:

    This grey paint thing is upside down theory, surely? According to the IPCC, carbon dioxide will simply reflect the radiated pavement heat back down to Earth anyway. Or is this another branch of grey science! Common sense says conducted heat to air and convection gets rid of the heat more efficiently than radiation. Maybe solar driven fans on the sidewalks would be a cooler idea than grey paint? Add a nice water mist spray and you’d also clean up air pollution. Just using some grey cells! As an aside, what happened to the French solar panel road idea?

  7. oldbrew says:

    ‘According to the IPCC, carbon dioxide will simply reflect the radiated pavement heat back down to Earth anyway.’

    So it will be bouncing up and down all day 😉

  8. The Badger says:

    Reduce the heat in the surface by changing the surface “coating”. I think we did this in the physics lab at school. In those days CO2 was only in the biology lab. It probably diffused across the corridor over the last 40 years, a lot of it seems to be in the staff common room now.

  9. Streetcred says:

    So this paint proves the effect of UHI … rocket, anuz !

  10. oldbrew says:

    Britain doesn’t need to coat the roads, this year at least…

    Date: 14/08/17 Paul Sims, The Sun

    Temperatures in London have failed to get any higher than 73F (23C) since schools broke up on July 19.


    Where’s our ‘global’ warming?

  11. Ian says:

    What about the source of the paint? Surely it’s not oil-based?

    Think about the implications for ambulance chasers ($$$$$) when somebody’s hurt when a car skids on the painted surface.

  12. Dodgy Geezer says:

    So this paint reflects the heat?

    Where does the heat go? Surely not all vertically? I suspect that a reflective road would heat up the houses around it something chronic… thus costing them more in air conditioning charges. Will they be able to bill the Highways Authority?

  13. steverichards1984 says:

    Law of unintended consequences:

    Scientists in Berkeley Lab’s Heat Island Group, in collaboration with the UC Pavement Research Center (UCPRC), the University of Southern California (USC), and thinkstep Inc., conducted life cycle assessments of conventional and cool pavements. Looking at the technologies over a span of 50 years, including manufacture, installation, use, and disposal/recycling, they found that the extra energy and emissions embodied in cool pavement materials usually exceed the expected energy and emissions savings from reduced space conditioning (cooling and heating) in buildings.

    Read more at: https://phys.org/news/2017-05-cool-pavements-equal.html#jCp

  14. oldbrew says:

    Re the French ‘solar road’ panels, they cost 4-6 times as much as putting the same amount of panels on rooftops. And panels work best when tilted towards the sun.


    But they might work in the dark if they get enough headlights on them 😂