Project Team
Student(s)
Stefan Korfmacher
Architecture
Brown University
Mentor(s)
Architectural Engineering
Architecture
Project Video
Project Abstract
The Urban Heat Island (UHI) effect is a well-documented phenomenon where urban areas may experience temperatures between 1 and 10 C higher than their rural counterparts and retain this heat longer into the night. The UHI is primarily a result of reduced evapotranspiration from vegetation cover and highly solar-absorptive materials in urban environments. High urban temperatures have significant ramifications for public health, increasing the incidence and severity of heat-related illness, and for sustainability, increasing building power consumption by 2-4% for every degree Celsius increase in urban temperature. A rich body of research exists on the efficacy of individual heat island mitigation strategies, but few exist determining hierarchies and second order effects of potential interventions. Screening masterplans for the proposed Pine Hall development in State College, Pennsylvania, we conduct Morris and Sobol sensitivity analyses using inputs in the Urban Weather Generator, a fast and well validated program for simulating UHI effects in urban microclimates. From these variables, EPWs generated for the current masterplan and improved and worsened UHI mitigation scenarios were input to Energy Plus to assess the impact of UHI on building hourly power consumption and carbon emissions. Our analyses predict the greatest reduction in UHI can be expected from reducing pavement thickness, followed by reducing the vertical to horizontal aspect ratio of buildings. Importantly, while increasing surface albedo is a popular mitigation strategy, alterations to surface albedo were among the least influential factors studied. The Energy Plus simulations reveal that the total building electricity demand increases while natural gas demand decreases, leading to a net decrease in energy demand between 1.28 and 3.69 percent. However, incorporating marginal emissions factors with these results exhibits an increase in CO₂ emissions across all UHI mitigation scenarios. Our methods provide an architect and planner-accessible framework for evaluating new construction or potential interventions to mitigate their UHI and subsequent carbon impacts, and the derived hierarchy provides a starting point for designers proposing new construction.
Project Poster
https://sites.psu.edu/climatedrawdown2020/files/formidable/6/Project-Poster.pdf