In 2019, New York City took a bold step toward climate action with Local Law 97, one of the most ambitious building decarbonization laws in the country. The law’s first year of implementation in 2024 has placed significant pressure on building owners to take meaningful steps in addressing emissions and improving reporting practices. With over 50,000 buildings subject to LL97, energy usage is under close scrutiny, and penalties for non-compliance are set to take effect in 2025.
Beyond the sheer numbers, LL97 has sparked crucial conversations among property owners, government agencies, and sustainability advocates about what it will take to collectively tackle decarbonization. However, this observation year has revealed significant challenges that could undermine the law’s success—burdensome compliance costs, vague rulemaking, and inconsistent emissions data are all hurdles that require urgent attention and refinement.
When LL97 came into being it was understood the costs to modernize New York City’s buildings would be astronomical. Yet, over the past five years, companies like BlocPower, Kelvin, Parity, and Runwise have pioneered financing mechanisms tied to future energy savings that can eliminate upfront costs and create an economically viable path to compliance, paid for through energy savings. These solutions show that compliance doesn’t have to be prohibitively expensive, but there is still a major need for additional financing solutions.
Progress has been further stalled by unclear, inconsistent, and delayed rulemaking from the Department of Buildings. Frequent and sometimes contradictory updates have left building owners and decarbonization service providers like Kelvin grappling with uncertainty, eroding trust in the process and delaying projects. For building owners, the misconception that LL97 compliance is synonymous with unaffordable upgrades persists.
More robust communication from the city, as well as expanded rebate programs and clearer guidelines, could help dispel these myths and enable property owners to take meaningful action.
Another significant challenge is the city’s reliance on self-reported emissions data, which can often be inaccurate. Without standardized measurement tools and stricter parameters for data submission, compliance tracking risks being undermined by poor-quality information. Addressing this gap is critical for creating an enforcement system that is both fair and effective.
The city itself has struggled to manage the volume of data and track compliance effectively, highlighting the need for enhanced resource allocation and a streamlined approach to enforcement as 2025 approaches. With penalties looming for non-compliance, enforcement has underscored the urgency for more informational resources, partnerships, and incentives, including more easily accessible rebates.
While LL97 is groundbreaking, New York City is not alone in its climate ambitions. Cities like Boston, Washington, D.C., and Denver have introduced similar building decarbonization mandates, with more municipalities likely to follow. This positions New York to lead by example, setting a national standard that other cities can adopt to accelerate the transition toward sustainable urban infrastructure. However, for LL97 to serve as a true blueprint, the city must address its early missteps.
By enhancing rulemaking transparency, investing in accurate emissions measurement tools, and expanding financial incentives, New York can ensure compliance is both achievable and scalable. LL97 holds the potential to transform the city’s building stock into a global model of sustainability, but only if policymakers, industry leaders, and property owners collaborate to overcome its challenges. Together, they can create a framework that balances ambition with practicality—solidifying New York’s role as a leader in both vision and execution, while inspiring cities nationwide to join the fight against climate change.
The writer is the vice president of business development at Kelvin, a climate tech company focused on decarbonizing legacy radiator-heated buildings.
