Decision Methodology for Temperature Control of Pavements

About 2.5 million miles of paved roads, which would cover an area about the size of the state of Georgia, exist in the United States. Pavements accumulate and dissipate solar energy in daily cycles. The increased heat in the pavement has many detrimental effects, including the accelerated degradation of the pavement, which results in increased costs to departments of transportation, and urban warming, which results in increased costs for cooling nearby inhabited structures and possibly contributes to microclimate change. Techniques such as heat exchangers that capture heat energy and transfer it to other forms of energy can reduce the extreme temperatures in pavements. Laboratory and some small-scale field trials of these systems have been conducted; however, the technology has not received wide implementation to date. Challenges to such implementation include limited documentation on the effectiveness of pavement cooling, a lack of accepted standard designs, a lack of evidence of long-term performance, the need for more efficient heat exchangers, and the cost of the system. Technological developments are rapidly overcoming the challenges, and the potential benefits of energy recovery are significant and include extended pavement life, reduced energy consumption in areas surrounding the pavement, improved air quality, the production of energy that could be used for other applications, and reduced microclimate impacts. This paper presents a decision methodology that would help designers and stakeholders evaluate, in terms of performance and cost measures, alternatives for systems to control pavement temperatures.