September 26, 2014 | Katie Weeks


This past week was packed with headline-making news including a historic public march demanding global action on climate change and a United Nations summit dedicated to climate issues—and New York City served as the hub for much of the developments.

Before hundreds of thousands of people took to Manhattan streets to march for action on climate change, Mayor Bill de Blasio and the New York City Council both committed to reducing the city’s greenhouse gas emissions (GHG) by 80 percent from 2005 levels by the year 2050—the target that the United Nations estimates is necessary to avoid the worst effects of climate change. It is an ambitious goal that supercharges the original PlaNYC target of a 30 percent reduction by 2030, and the commitment establishes New York as the largest global city to take a “80 by 50” pledge.

Meeting “80 by 50” targets will require an unprecedented level of investment in building energy efficiency, and Mayor de Blasio’s announcement coincided with the release of New York City’s third annual Local Law 84 Benchmarking Report. Nearly three-quarters of New York’s GHG emissions come from its buildings and the continued tracking and reporting of building energy use is critical to understanding how to reduce emissions.

The new report analyzes building energy use data from 2012, collected from more than 23,000 buildings representing more than 2.1 billion square feet of space. The report offers a wealth of data. “The city has analyzed the largest set of privately owned building energy and water use data of any single jurisdiction in the U.S., and we now know much more about our buildings than was ever possible before.” You can read the full report here. For now, however, let’s take a look at a few takeaways and what they may showcase in light of New York’s new emissions goal.

  • Reporting compliance is on the rise. Not only are more building owners reporting their energy and water use to the city, but they’re also now showing consistency in doing so year over year. Of the more than 23,000 buildings required to benchmark under Local Law 84, 84 percent complied in 2013 (a 9 percent increase from 2011) and 92 percent of the building owners in 2011 continued to file in 2013. More compliance means more consistent data year over year, which should help to better identify abnormalities (such as a Hurricane Sandy-type event that may have skewed data reporting for some regions in 2012) and large-scale trends and opportunities for reductions. Compliance is essential for reaching longer-term emissions reduction goals because, as the adage goes, you can’t manage what you don’t measure.
  • City-wide reported energy use is on the decline. The median office energy use intensity (EUI), the amount of energy a building uses per square foot, is down 13 percent from Year 2, and the median multifamily EUI declined 12 percent. However, it is important to note that the data set between the two years is not consistent enough to claim that there has been a dramatic decline at scale—this is why the increased year-to-year compliance rate is critical to getting consistent and actionable data.
  • Data needs to be examined with an eye on uncommon variables.The effects of Hurricane Sandy continue to be felt in the New York region and the super storm looms large over the 2012 data. The storm had a tremendous effect on waterfront properties, with coastal flooding damaging electrical equipment and leading to power losses lasting more than three weeks. When the full data set was cleaned of properties in the storm inundation areas that faced long-term power losses and reduced operational capacity, the sample size that was consistent from Year 2 to Year 3 dropped dramatically. The report notes that the reduction in properties factors into inconsistencies seen in the Year 3 data set.
  • Multifamily buildings remain ripe with potential. In analyzing last year’s data, we noted the importance of focusing on improving the city’s multifamily building stock and it continues to hold true. Multifamily buildings represent 75 percent of the benchmarked properties, cover 64 percent of the gross floor area that was benchmarked, consume 64 percent of the total energy used, and are responsible for over half of the GHG emissions attributed to the measured buildings. On the upside, multifamily properties reported a median EUI of 121 in 2012, lower than the national median source EUI of 130, as determined by the Residential Energy Consumption Survey 2005 database. One of the challenges in reaching this sector, the report notes, is that it is “the most difficult to initiate investments in building improvements due to governance structure among owner-occupied properties and limited tenant control among rental properties.” The latest batch of data, however, is helping the city to identify construction types and systems characteristics in the multifamily sector to better direct policies and programs toward the greatest energy efficiency opportunities.

We’re just scratching the surface of the insights offered by this year’s data and we expect to learn more about how New York’s buildings are using energy as we take a closer look at the numbers. In addition, in the coming weeks New York City will also release the energy and water use data for all properties that are required to benchmark. The data being collected and analyzed will continue to grow, not only in New York, but also across the country as more cities prepare to report on their own datasets. Benchmarking laws like the ones passed in New York and a growing number of other U.S. cities are bringing an unprecedented level of transparency to the real estate market and getting building owners and operators to “step on the scale” and pay better attention to their energy use. The resulting wealth of data is an essential tool in devising solutions to meet our climate goals, such as New York City’s 80 percent emission reduction target, and benchmarking and transparency policies will continue to lay the foundation for better buildings.


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Meet the Author

Katie Weeks

Former Managing Director of Development and Communications

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