When White means Green (the white roof movement)
(image by Gatewaygreen.org)
There’s a movement going around called the “White Roof Movement” which says that painting your roof white can help save the environment and your wallet. The idea is that a white roof, having a higher solar reflectance (reflection of ultraviolet rays to reduce heat transfer), leads to less heat being absorbed by your roofing system and thus lessening the need for air-conditioning.
I guess this is fairly similar to wearing a black shirt compared to a white shirt on a hot sunny day.
Anyway, much research and news has come from all over about this topic:
In the US, the New York times says:
"Studies show that white roof reduce air-conditioning cost by 20 percent or more in hot, sunny weather. Lower energy consumption also means fewer carbon dioxide emissions that contribute to global warming."
The Lawrence Berkley National Laboratory says:
"White roofs save building’s cooling-energy use by about 20% (and hence directly reduce CO2 emissions from electricity generating power plants). The estimated U.S. potential savings for white roofs are in excess of $1 billion per year in net annual energy bills."
In Malaysia, a study entitled: “The Investigation of Green Roof and White Roof Cooling Potential on Single Storey Residential Building in the Malaysian Climate” by Asmat Ismail, Muna Hanim Abdul Samad and Abdul Malek Abdul Rahman, says that:
"the maximum average temperature difference between black bare roof and white roof was only 0.97degC between 10 o’clock in the morning and 12 midnight with the maximum value of 1.16degC recorded at 7.45pm average indoor surface temperature difference between white roof and black bare roof was only 5.30degC."
Here in the Philippines,
Siliman University is being backed up by Smart communications to pilot test the movement in Cebu.
I believe this might be a worthwhile endeavor, considering that paint is only about Php600 per gallon, while it can potentially reduce temperatures by 1-2 degrees indoor air temperature possibly saving about 20% in cooling energy.
With the country gaining the distinction of having the most expensive electricity rate in Asia, I believe this movement will benefit our country, not only in terms of being responsible with our environment, but also with actual savings in our monthly electrical bill