Cool surface technologies, urban vegetation, and their effects on energy and air quality in Canadian climates

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During the summer, cool roofs reflect most of the incoming sunshine and reduce heat conduction through roofs. Similarly, strategically placed trees, shading windows and walls of a building reduce the direct heat gain. The reduction in summer heat gains reduces the air-conditioning load of a building, improves comfort, saves peak demand electricity, and save money. During the winter, cool roofs and shade trees may add to the heating load of a building, however, the heating energy penalties are fairly small (trees can actually save heating energy bills by shielding a building from cold wind).***Summertime temperatures in many Canadian cities have been steadily increasing with expansion of the city. Also, most new buildings are equipped with air-conditioners; as a result the local utility companies are experiencing significant summertime peak load. Cool urban surfaces together with vegetation can potentially cool down the city by a few degrees, further reducing cooling energy demand, improve ambient air-quality, and reduce summertime heat stress related mortality. Also, data suggest that cool roofs and cool pavements may last longer than the hot standard materials, lower life-cycle cost and lower waste. ******Increasing the solar reflectance of urban surfaces, in addition, increases reflection of short-wave radiation back to space. This process of "negative radiative forcing" counters global warming. IPCC estimates that increasing the solar reflectance of a m2 of surface by 0.01 cools down the globe equivalent to reducing CO2 emissions by 7 kg. Increasing the reflectance of 50% urban areas by 0.10, cools down the world equivalent to 130 Gtonne of CO2 (~ 50 years of emissions from all cars). ******The objective of this project is to perform basic and applied research addressing energy efficiency and air quality appropriate to Canadian cold climates, buildings and communities. We will: Perform detailed analysis to characterize the effects of cool surfaces and vegetation on building and community energy use and urban air quality; Develop detailed land use databases for several Canadian cities (obtain high-resolution orthophotos and perform statistical analysis to characterize urban fabrics); Develop implementation programs for installing cool roofs, cool pavements, vegetation; Develop climate- and regional-specific cool roofing and cool paving materials appropriate for Canadian climate (in collaboration with roofing and pavement industry); Develop regional-specific correlation between increasing urban albedo and global warming; Assist local, states, and federal governments to develop regional energy codes, standards, implementation guidelines; and Seek and train research scientists, post-doctoral fellows, and graduate students with strong background and interest in buildings and community design, material development, climate and air quality modeling, and codes and standards development.**