Image provided by John Lee, NYC Mayor’s Office. Copyright ©2014  

OneNYC sets a target of reducing New York City’s greenhouse gas (GHG) emissions by 80% by 2050, compared to 2005 levels. The City’s Greener, Greater Buildings Plan (GGBP) is one of the world’s most comprehensive building energy efficiency policy packages, and supports the citywide target through four local laws. Local Law 84 (LL84) mandated owners of large buildings to annually benchmark1 and disclose their energy and water consumption. The other three laws address related issues, namely adherence to strict local energy codes for both new construction and retrofitting regardless of building size (LL85), audit2 and retro-commissioning3 every ten years (LL87), and lighting upgrades and installation of electric sub-meters for large tenant spaces in commercial buildings to facilitate compliance with the current energy code (LL88).  Although it only affects approximately 2% of total buildings in New York City, LL84 covers about half of the gross square footage, which is responsible for 45% of citywide energy consumption.

What is it?
Signed into effect in 2009, LL84 is the first law of the GGBP. It requires owners of large buildings (over 50,000 square feet) to annually measure and disclose their energy and water consumption using ENERGY STAR Portfolio Manager4 – a free, online benchmarking tool provided by the U.S. Environmental Protection Agency5.

How does it work?
The benchmarking programme requires owners of large buildings to report energy and water use data to the City by the beginning of May every year. As data for the whole building is required, owners must collect this directly from tenants or by requesting aggregated data from utilities. The City strongly recommends the latter method. The water usage mandate is only applicable to those buildings equipped with automatic meter readings provided by the Department of Environmental Protection (DEP). Upon the building owner’s request, this data is automatically uploaded to ENERGY STAR Portfolio Manager by DEP.

The City has evaluated and compiled the data into a series of annual benchmarking reports for the first three years. These reports analyse compliance levels and data quality in addition to energy and water consumption trends. Although there is presently no third-party verification process, the City does conduct data cleaning with cooperation from academic partners.

Currently, fines are only applicable to cases of non-compliance. As benchmarking results are disclosed on the City’s website by the NYC Department of Finance (DOF), owners failing to comply are also publically listed.

CO2 reduction
According to the second annual report for the benchmarking programme, a 75% compliance rate was achieved in both 2010 and 2011. In 2012, compliance rose to 84%. Compared to year one, median ENERGY STAR scores for year two have also increased from 64 to 67, out of 100.

The benchmarking scheme was enacted in late 2009 and implemented by the private sector in 2011 for data from the calendar year 2010. As such, it is too early to assess the impact of the programme on the retrofit market or demand for energy efficient buildings. In terms of other market impacts, however, the Institute for Market Transformation (IMT) reports that a growing number of companies have started offering services related to benchmarking and auditing.

Next steps
The City recognises that manual data entry is a short-term approach, with direct uploading being the end goal. The City is thus actively exploring partnerships with utilities and the federal government to make automatic energy data uploading feasible in the near future. It has seen success with water data, as DEP has been providing direct and automatic uploads since 2011.

Local Law 84 (along with LL87) has helped establish one of the largest collections of building energy performance datasets in the world. This data is invaluable for highlighting energy savings opportunities, informing the City’s future energy efficiency policies, and supporting market transformation through information transparency.

Further information
To find out more about New York’s mandatory benchmarking scheme, the programme’s success factors, challenges and lessons learned please refer to the report Urban Efficiency: A Global Survey of Building Energy Efficiency Policies in Cities launched by the Tokyo Metropolitan Government and C40 in late 2014 and updated in May 2015.


 1Energy benchmarking enables building owners to track their properties’ energy consumption and assess it against like-for-like top performance.

The inspection, survey or examination of a building or facility to identify current performance and efficiency improvement opportunities.

Retro-commissioning is a systematic process used for the identification and implementation of operational and maintenance improvements in existing buildings.

Portfolio Manager is a free online tool provided by the U.S. EPA that enables building owners and managers to track and assess energy and water use across their entire portfolio of buildings.

 Environmental Protection Agency or EPA is the federal U.S. agency responsible for protecting and improving human and environmental health.

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