The city had enormous power to implement policies that directly affected millions of residents—something that was especially apparent to Hsu in his role coordinating the rebirth of Lower Manhattan after the September 11 attacks. This responsibility was counterbalanced, though, by a frustrating truth. “I always felt like we didn’t have enough information,” says Hsu, since 2015 an assistant professor in MIT’s Department of Urban Studies and Planning. That’s what inspired him to enter academia. “I hope to bring a lot of academic rigor to that conversation.”
When Hsu finished his PhD, he reached out to his former colleagues in New York City to see how academic research could advance the city’s environmental goals. New York City had recently implemented an energy benchmarking policy that collected and published information about the energy use in the city’s 10,000 largest buildings. The policy’s goal was to create greater transparency for prospective buyers and tenants, to factor such information into property values, and above all to inspire building owners—many of whom had not, themselves, had previous access to such comprehensive data— to make energy improvements.
At the time, this was an untested strategy. City officials had a trove of data that they didn’t know how to use or interpret. They asked Hsu to help in the effort to analyze and present the information efficiently. His findings were remarkable: the energy benchmarking policy reduced energy use in studied buildings by between 12% and 14% in four years. Similar benchmarking policies have now been adopted in 27 cities and two states, and are being actively promoted by the Department of Energy, the Environmental Protection Agency (EPA), and many environmental advocacy groups. These policies are influenced not only by New York City’s success, but also by Hsu’s research on how to improve benchmarking data and EnergyStar ratings, and how to use data-driven statistical learning to make accurate comparisons between diverse buildings.
Based on his experience studying the role information plays in encouraging investment in green infrastructure, Hsu was awarded a grant from the EPA to study barriers to implementing the Green City, Clean Waters program in Philadelphia. The program aims to avoid an expensive new sewer system by using fees and subsidies to encourage private property owners to build green infrastructure, such as rain gardens, to manage stormwater on 10,000 acres, or about a third of the city. Upon discovering that the biggest barrier to participation was lack of information regarding the costs, benefits, and logistics of adopting such infrastructure, Hsu and his team developed a prototype for a web portal that will provide property owners with information about how to reduce their fees, as well as connect them with contractors and financing sources. While Hsu’s involvement in the four-year project ended last October, the City of Philadelphia plans to expand the prototype into a full-fledged website within the next year.
With his research in New York City and Philadelphia winding down in 2017, Hsu is turning his focus toward electrical grids in both the developed and developing world, including studying experimental microgrids in India. He’s also working with several colleagues at MIT to study how policies and technology have contributed to the falling cost of solar panels, and is discussing options for studying several cities’ plans to reduce carbon emissions by 80% by 2050.
Helping cities understand what is and is not working is the cornerstone of Hsu’s ongoing research. “Urban environmental policy has a high impact on a lot of people,” Hsu says. “It’s honestly where the battle to mitigate climate change is going to happen.”