How are NYC’s buildings doing in cutting emissions?
Addressing climate change means addressing energy use in buildings. Two-thirds of New York City’s greenhouse gas emissions come from this sector, and the city needed reliable data to create effective policy to reduce emissions and track progress. Enter benchmarking. In 2010, New York became one of the first American cities to collect data about the energy and water used by large buildings. Urban Green was closely involved in creating and promoting the initial benchmarking law 10 years ago, and after a decade, NYC’s benchmarking dataset is the largest and most comprehensive in the country. More important, New York has successfully leveraged this data to implement innovative policies that promote energy efficiency and reduce emissions.
- Emissions fell more than 23 percent and energy use fell more than 8 percent for regularly benchmarked properties.
- Energy efficiency was responsible for 35 percent of the emissions drop.
- Switching to cleaner fuels contributed 25 percent.
- A cleaner grid accounted for 40 percent.
New York City’s 2020 Energy and Water Use Report created by Urban Green Council presents a trend analysis of 10 years of benchmarked energy and emissions, evaluates the energy and water use of midsize buildings for the first time and assesses the progress NYC’s benchmarked building stock has made towards citywide decarbonization goals and mandates.
A decade of data
For the 3,120 large properties that benchmarked regularly over the past decade (that is, submitted data at least nine out of 10 years), emissions fell more than 23 percent and energy use fell more than 8 percent. Urban Green observed similar trends across all benchmarked buildings.
This impressive reduction was driven by multiple factors, including cleaner electricity generation, improved district steam production and delivery, accelerated fuel switching, more efficient energy use, and variable weather. Urban Green found that energy efficiency improvements to buildings were responsible for more than one-third of this emissions drop, while switching to cleaner fuels—notably from fuel oil to natural gas—accounted for 25 percent. The remaining 40 percent of the decrease came from electricity and district steam generation.
More natural gas, less fuel oil
New York City buildings have gone through an epic transformation in energy sources since 2010. Natural gas has replaced heavy fuel oil as the primary fuel used for heating in most benchmarked buildings; fewer than 100 properties reported using any heavy fuel oil in 2019, compared to 2010 when it made up almost one-quarter of the total.
Since heavy fuel oils emit large amounts of soot and sulfur dioxide in addition to CO2, this transformation has reduced carbon emissions and improved air quality. Unfortunately, these improvements are not evenly distributed across the city. Neighborhoods that still use heavy fuel tend to be concentrated in northern Manhattan and the Bronx. This is an environmental justice concern, given that these areas are predominantly made up of lower-income communities of color.1
Adding midsize to the mix
In 2017, benchmarking expanded to include midsize buildings (25,000–50,000 square feet), adding roughly 9,000 properties for a total of 25,000 properties encompassing more than 3 billion square feet in NYC. We found that 68 percent of New York City’s benchmarked buildings are smaller than 100,000 square feet. Together, they account for just one-third of the benchmarked floor area.
The addition of midsize properties provides insight into how smaller buildings differ from larger ones. The overwhelming majority of midsize buildings are used for multifamily housing, and this sector consumes significantly more energy and water per square foot than their larger counterparts: their median site energy use intensity is 15 percent higher. As a large contributor to NYC’s overall resource use, this sector deserves additional attention.
Local Law 33 of 2018 seeks to make all New Yorkers aware of differences in building energy use in order to boost energy efficiency efforts. In October 2020, benchmarked buildings received a Building Energy Efficiency Rating based on their 2019 energy use. These grades are based on the Environmental Protection Agency’s ENERGY STAR program, which ranks the energy performance of buildings by comparing them to similar buildings with the same primary use nationwide. The grading scale implemented by the city is as follows:
- A score is equal to or greater than 85;
- B score is equal to or greater than 70 but less than 85;
- C score is equal to or greater than 55 but less than 70;
- D score is less than 55;
- F for buildings that didn’t submit required benchmarking information;
- N for buildings exempted from benchmarking or not covered by the ENERGY STAR program.
Urban Green found that better Building Energy Efficiency Rating letter grades usually correspond to lower carbon intensities in benchmarked properties. Specifically, the median carbon intensity of a building receiving an A grade is less than the median carbon intensity of a building receiving a B grade. This was true for every grade tier and property type. In 2019, offices were the best performers, with almost half of all properties receiving an A or B grade.
This report was possible thanks to generous support from Carrier.
The latest analysis of NYC's building energy and water use data.
NYC site energy use and carbon emissions both decreased in 2020.
We used the 2014 and 2015 New York City building benchmarking data to explore energy use in NYC buildings.