The NYU Marron Institute study finds modest reductions in residential and office building energy use in the wake of the city's audit requirement.

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­­­­­­New York City’s pioneering Local Law 87 requires buildings to monitor their energy use, using detailed audits. In an article published today (March 30) in the research journal Nature Energy, Constantine E. Kontokosta of New York University and fellow researchers discuss the impact of this requirement on building owners, looking closely at detailed audit data between 2011 and 2016 for 4,000 buildings. As a result of the law, the researchers found, energy use fell by a modest -2.5% for multifamily residential buildings and -4.9% for office buildings.

“The results suggest that mandatory audits, by themselves, create an insufficient incentive to invest in energy efficiency at the scale needed to meet citywide carbon-reduction goals,” wrote Kontokosta and coauthors Danielle Spiegel-Feld and Sokratis Papadopoulus. “In the context of a comprehensive, data-driven energy policy, audit requirements can be used to target ‘deep’ retrofits, while automated or virtual audits could replace the existing need for traditional audit mandates."

Energy use in existing buildings, according to th­­­e article, is responsible for an estimated 67% of all New York City carbon emissions. More than 20 cities, including Austin, Chicago, and San Francisco, have adopted policies to increase data and transparency on energy use, seeking to encourage market interventions to reduce energy consumption and carbon pollution. New York City has led the way in this regard.

The New York University Marron Institute study, supported with grants from the National Science Foundation and the Sloan Foundation, seeks to inform urban energy policy decisions by comparing energy use in properties that have performed a mandatory energy audit with those that have not within New York City.

The article, titled “The impact of mandatory energy audits on building energy use,” is coauthored by: Kontokosta, associate professor of urban science and planning, and director of the Civics Analytics program, NYU Marron Institute of Urban Management; Spiegel-Feld of the Guarini Center on Environmental, Energy and Land Use Law, NYU School of Law; and Papadopoulus, NYU Tandon’sDepartment of Civil and Urban Engineering, and Center for Urban Science & Progress (CUSP).

To speak with the authors, contact the NYU press officer listed with this release.