Urban heat islands are associated with high temperatures leading to increased demand for air conditioning and thus energy use. Link to: High Temperatures and Energy Use. The Heat Island Group's Haider Taha performed a computer meteorological simulation of the Los Angeles area which consists of approximately 10,000 km2 of urban area, of which 1,250 km2 is pavement. Taha found that by changing the albedos (reflectivities) of pavements to 0.25 we can reduce temperatures by 1°F (0.6°C). Link to: Pavement Albedo and Cool Pavements Lower Temperatures.
This reduction in temperature would reduce the heat island effect and save energy by reducing the demand for air conditioning. Taha simulated the energy used by buildings using this resulting cooler air temperature in four seasons and interpolated over the entire year. Compared to the energy use in normal temperature, the Los Angeles urban area would save $15 million per year. We obtain a similar result using power demand vs. temperature curves.
The cooler air resulting from cooler pavements would also affect the generation of smog (ozone), which is known to be dependent upon temperature. Link to: Air Quality. Simulations for the Los Angeles area project that the lower air temperature due to cool pavements reduces smog by about 2.5% of the exceedance of 90 parts per billion (from the California Air Quality Standards). The value of this smog reduction is about $75 million per year (Hall et al., Science 1992).
Thus we estimate that the energy and smog benefits of pavements in Los Angeles would be $90 million per year. For 1,250 km2 of cooler pavement, that's only $0.07 per m2 per year. A thin resurfacing can last for at least 5 years, so if the present value of additional cost of a whiter pavement is less than $0.35 per m2, the pavement benefit pays for itself.
Cooler pavements also have longer lifetimes because they are not as stressed by the excessive heat. Pavements than are more durable save money by reducing the need and associate expense of repaving. Link to: Pavement Durability.
For an overview of some benefits of low-albedo (cooler) pavements, link to: "Benefits of Cooler Pavements"