Local Laws 84 & 97: NYC Energy Benchmarking, Carbon Caps, and 2024+ Fines
13 min read · Updated 2025-01-15
NYC Local Law 84 requires annual energy benchmarking and Local Law 97 imposes carbon emission caps with fines starting 2024. Learn who is covered, how to comply, and how to reduce your building's emissions.
Local Law 84 — Annual Energy Benchmarking
What is NYC Local Law 84?
Local Law 84 (LL84) requires owners of large buildings in NYC to annually measure their energy and water consumption — a process called benchmarking — and report that data to the city using the U.S. EPA's ENERGY STAR Portfolio Manager tool. The law applies to most buildings 25,000 square feet or larger (and groups of buildings on the same lot that exceed 100,000 sq ft combined). LL84 data is publicly disclosed, so tenants, investors, and buyers can compare a building's energy performance against peers.
When is the LL84 benchmarking filing deadline?
The annual LL84 filing deadline is May 1. You're reporting the prior calendar year's energy and water data. So the May 1, 2025 deadline covers January 1, 2024 through December 31, 2024 utility data. You must collect utility data from Con Edison, National Grid, the NYC DEP water authority, and any other utility providers and upload it to ENERGY STAR Portfolio Manager, then submit the compliance report through the NYC benchmarking portal.
What data do I need to submit for LL84?
You need 12 months of utility data: electricity (in kWh), natural gas (in therms or Ccf), fuel oil (if applicable, in gallons), district steam (in Mlb), and water (in gallons). You'll also need the building's gross floor area by property use type, number of occupants or units, and operating hours. Utility providers can often provide data directly in a format compatible with ENERGY STAR Portfolio Manager. Con Edison and National Grid both have web services that automate the transfer.
What is the penalty for missing the LL84 deadline?
Failure to submit the LL84 benchmarking report by May 1 results in a fine of $500 per quarter that the building remains non-compliant, up to a maximum of $2,000 per year. While not enormous, these fines accumulate and the non-compliance is noted in public disclosure. More importantly, LL84 data is the foundation for LL97 compliance analysis, so failing to benchmark means you're flying blind on your carbon compliance status.
Local Law 97 — Carbon Emission Caps and Fines
What is NYC Local Law 97?
Local Law 97 (LL97) of 2019 is one of the most ambitious building decarbonization laws in the world. It sets mandatory carbon emission limits (measured in tons of CO2 equivalent per square foot) for most NYC buildings over 25,000 square feet. Buildings that exceed their cap must pay fines of $268 per ton of excess emissions starting with the 2024 reporting year (filed in 2025). The emission caps tighten significantly in 2030 and again in 2035, requiring substantial energy retrofits for many buildings.
When did LL97 fines start?
LL97 fines apply starting with calendar year 2024 emissions. Building owners must file a compliance report for 2024 by May 1, 2025. If your building emits more than its allowed limit during 2024, you owe $268 per excess ton of CO2e. LL97 is not theoretical — the first compliance period is now. Buildings that haven't analyzed their exposure are at risk of receiving unexpected and potentially very large bills.
How are LL97 emission limits calculated?
LL97 emission limits are expressed as a carbon intensity metric: metric tons of CO2e per square foot of gross floor area, multiplied by the building's total area. Each property use type (office, multifamily residential, hotel, retail, etc.) has its own carbon intensity limit. Mixed-use buildings must calculate a blended limit proportional to their mix of uses. The limits become more stringent in 2030 and 2035, meaning even buildings currently in compliance may need further upgrades in future periods.
What are the strategies to reduce LL97 penalties?
Key compliance strategies include: switching from steam or oil heating to electric heat pumps, upgrading to LED lighting and efficient HVAC controls, improving building envelope insulation and window performance, purchasing Renewable Energy Credits (RECs) recognized by the law, signing a utility green power purchase agreement, or purchasing carbon offsets through the city's approved programs. Buildings with high fuel oil usage tend to have the worst LL97 exposure. An energy audit by a licensed energy consultant is the starting point for any compliance strategy.
Are there any LL97 exemptions or adjustments?
Yes. Several adjustments are available. Buildings that are "stranded" (where the technology to reduce emissions doesn't yet exist at reasonable cost) can petition the NYC Department of Buildings for an adjustment. Buildings with registered affordable housing that meet certain affordability thresholds may qualify for a higher emission limit. Buildings owned by the city, state, or federal government follow different rules. Religious institutions and certain non-profits have sought exemptions but most are still subject to the law.
What is a LL97 compliance report and who files it?
The LL97 compliance report (also called the Building Emissions Report or BER) is filed annually with DOB by May 1. It's completed by a registered design professional (PE or RA) who certifies the building's actual emissions based on the LL84 benchmarking data and utility bills. The report calculates whether the building is under or over its emission limit and quantifies any penalty owed. Fines are paid to the NYC Department of Finance.
How do I convert LL84 benchmarking data into LL97 compliance analysis?
Each fuel type has a carbon emission factor that converts consumption (kWh, therms, gallons, Mlb) into CO2e tons. Electricity emissions use a time-varying factor based on the NYC electrical grid mix. Natural gas, fuel oil, and steam each have fixed factors. Your design professional multiplies consumption by the relevant factor, sums all fuel types, and compares the total to your building's allowed limit. The math is complex enough that most owners hire an energy consultant or use specialized software for the analysis.
What buildings are exempt from LL97?
Buildings under 25,000 gross square feet are not covered. One- to three-unit residential buildings are exempt. City-owned buildings follow a separate framework. Religious institutions and some non-profits have partial adjustments. Buildings designated as affordable housing under Section 8 or other subsidy programs may qualify for adjusted limits. Landmark buildings may receive adjustment provisions in certain circumstances. However, these exceptions are narrow — most large NYC buildings are covered.
Can I sell carbon credits to reduce my LL97 liability?
LL97 does not currently have a cap-and-trade market where you can sell excess allowances if your building is under its limit. However, the law does allow certain buildings to purchase "deductions" through DECKs (Distributed Energy Resource Credits) or through solar renewable energy credits. The city has been developing a carbon trading program, but as of 2024, the primary compliance pathway is physical emission reductions or approved offset purchases — not selling credits to other owners.