The fight against climate change has taken a rather low-tech turn lately.

• Obama’s Energy Secretary Stephen Chu wants to fight climate change by whitewashing the world’s roofs roads and pavements.
• California’s air regulators are requiring automakers, beginning in 2012, to install sun-reflecting glass in the windows of new cars sold in the state to help cut cooling needs.
• And in New York City, council members passed legislation requiring businesses to close their doors when they have the AC running.

These measures may lack the cutting edge appeal of a solar airplane or a Tesla, but they could make a much bigger difference. Secretary Chu explained to the UK’s The Times that his friend, and member of the California Energy Commission, Art Rosenfeld, had run the numbers on the effects of painting the world white.

“Now, you smile, but he’s done a calculation, and if you take all the buildings and make their roofs white and if you make the pavement more of a concrete type of colour rather than a black type of colour, and you do this uniformly . . . it’s the equivalent of reducing the carbon emissions due to all the cars on the road for 11 years.”

Since light surfaces reflect up to 80% of sunlight, compared with the 20% reflected from dark ones, whitewashing is proven cooling tech (for evidence, see a video I shot of the traditional green building techniques, including whitewashed homes, in Extremadura, Spain). Rosenfeld helped push through white roof legislation in the state of California back in 2005. Since then, all flat-roofed commercial buildings have been required to have white roofs and this year, that requirement will be expanded to both flat and sloped roof residential and commercial buildings.

Rosenfeld and his colleague Hashem Akbari would like to go global with their geoengineering idea. Given that 25% of most cities worldwide are roofs and about 35% is pavement, lightening these surfaces is a “win-win-win“, explained Akbari to the LA Times. “First, a cooler environment not only saves energy but improves comfort. Second, cooling a city by a few degrees dramatically reduces smog. And the third win is offsetting global warming.”

Low carbon AC: heat reflective windows

Just last week California regulators announced they were again leading the way with another example of enforcing a bit of old tech. For two decades we’ve had the technology to make car windows more reflective and reducing the need for AC, but the regulation by the California Air Resources Board (CARB) to require automakers to use it is totally novel.

Mandating that all new cars, starting in 2012, have windows that reflect the sun’s rays to reduce the need for climate control is just “common-sense“, argues CARB Chairperson Mary D. Nichols. “It represents the kind of innovative thinking we need to reduce greenhouse gas emissions from our vehicles and steer our economy toward a low-carbon future.”



The lower demand for AC should also prevent about 700,000 metric tons of CO2 from entering the atmosphere in 2020, what the Green Car Congress says is roughly the equivalent of taking 140,000 cars off the road for a year.

Originally CARB was pushing a “cool paint” initiative, or a requirement that all cars use heat-reflecting paints, but automakers complained that the technology, especially for black cars, wasn’t ready yet. So instead, the industry will be forced to use a more proven technology- either solar absorbing glass or infrared reflective glass- to block at least half of the sun’s rays from entering the vehicle.

This mandate- which could mean the end of overheated cars on hot summer days- will cost automakers just $111 per vehicle, but will save the user $16 in fuel savings per year, according to CARB estimates. The regulatory group also claims this relatively simply change will result in an average temperature reduction inside the car of 13°F. (For a visual of this technology, I recently shot a video including Renault’s Z.E. Concept vehicle that sports heat-reflecting windows. As you can see, the acid-green tinted glass will definitely garner attention).

Close The Door on climate change

It’s about as low tech as you can get in the fight against climate change: stores in New York City are being told to close their doors while running their AC, or face fines.

Last year, the New York City Council passed first-of-its-kind legislation requiring stores (businesses with at least 4,000 square feet and those that are part of a chain of 5 or more New York City outlets) to close their doors while running air conditioning in order to save energy. The bill’s chief sponsor Councilwoman Gale Brewer signaled the move as a part of changing times, helping to “make all of us participants in making our planet a better place.”

Asking businesses to shut their doors may not sound as sexy as installing rooftop solar, but it could help make the planet a bit better place. New York City utilities provider Con Edison estimates that if 1,000 businesses keep their doors open, they are wasting 4,600 barrels of oil and releasing 2,200 tons of carbon dioxide into the atmosphere. That’s the equivalent- in greenhouse gas emissions- of taking 425 cars off the road for a year.

This is the first summer where the legislation is in effect and businesses have complained that they will lose customers if they close their doors. But the director of the UK’s Close The Door Campaign, Jeannie Dawkins, who has been looking at the issue for a couple of years now, explained to me that based on internal company case studies, this “urban myth” doesn’t hold up.

“On investigation footfall does not equate so directly to profit as is often assumed by many managers – profit relies on a great many other more closely related factors. Somewhat surprisingly we have not seen a single negative effect to trading”. Dawkins elaborated in her email that a closed door can even help encourage customers to buy more given that the store’s climate is more comfortable and the “bustle of the street” is removed (For the full interview with Dawkins, see Climate control for sidewalks: making stores close the door).

While these types of lower-tech responses to global warming may not get the PR boost of a Prius, but they’re much easier- and cheaper- to implement and anyone can become a campaigner. “The customer’s voice and demands are very important – if made politely they have great effect,” says Dawkins. “We have found many instances of polite complaints filtering up to head offices from stores, where they are invariably taken seriously.”

So this summer, before buying the latest eco-gadget, consider painting your roof white, using sunshades on your car windows (an even lower tech option before we all switch to sun reflective glass) and telling a store manager to “close the door”, in a polite way of course.