By Steven Cohen, Ph.D., Director of the M.S. in Sustainability Management program, School of Professional Studies
New York City has evolved from a commercial trading hub, accelerated by the construction of the Erie Canal, to a manufacturing city, anchored by 500,000 garment workers in 1950, to the service city of today featuring finance, education, health, fashion, design, communication, tourism, entertainment, sustainability, and technology. As Dong Guo and I argued in the second edition of The Sustainable City back in 2021, New York is quietly making progress as it is gradually transforming into an environmentally sustainable city. The transition is subtle, just as the transition from manufacturing to services was largely misunderstood until it was nearly over. But it is underway.
The energy transition has started, and its progress has been gradual but substantial. Con Edison, New York City’s supplier of electricity and gas, has been working diligently to reduce its carbon footprint and increase its energy efficiency and that of its customers. While the city lags behind efforts to meet ambitious decarbonization goals, progress continues even in the face of federal opposition to renewable energy. Local Law 97, which calls for the gradual decarbonization of the city’s large buildings, is now an operational part of the city’s system governing its built environment. According to the Urban Green Council:
“Energy use and carbon emissions from NYC’s largest buildings have fallen over the past 13 years. These metrics vary from year to year due to multiple factors, including the fuel mix for electricity generation and variable weather. However, they have both trended down due to more efficient energy use, improved district steam production and delivery, and accelerated fuel switching.”
They report a “26% reduction in emissions from large buildings since 2010.” The city is phasing in requirements for all-electric new building construction and is working to reduce the fossil fuel content of its electric grid. Local Laws 92 and 94 promote solar and green roof installation. Green roofs can absorb heat and water and mitigate the impact of climate change and extreme weather events, while solar installations create carbon-free electricity. Solar energy installation in the city is still small, but increased from about 58 MW in 2015 to 572 MW last year. While that remains a modest share of the city’s energy needs, as power lines from upstate New York bring in hydro power, and when wind and solar power supplies are increased in the coming years, we will see growth in the grid’s renewable energy supply.
New York City’s government has self-consciously become a role model for decarbonization efforts. According to the city’s Department of Citywide Administrative Services:
“Local Law 97 (LL97) requires city government to reduce its GHG emissions further and faster than the private sector, continuing the tradition of the City leading by example. The law requires the City to achieve a 50% reduction by 2030, with an interim 40% target by 2025.The City has already completed over 14,000 energy conservation measures across 2,300 unique city government facilities over the past decade, leading to GHG reductions equivalent to removing 80,000 cars from the road and saving New York City taxpayers over $125 million in annual energy costs. Over the next decade, the City will invest an additional $6 billion to retrofit and electrify its buildings, install clean energy, and advance towards its 2050 goal of fossil fuel-free government operations… City government reduced its GHG emissions by 25% from a FY06 baseline as of the end of FY22, compared to a 17% reduction citywide, according to most recent New York City Inventory of Greenhouse Gases, which was published by the Mayor’s Office of Climate and Environmental Justice in November of 2023. Although the City is behind schedule due to unforeseen and unprecedented challenges over the past several years, we forecast that we will surpass the LL97 40% reduction target by 2027 and significantly exceed the 50% target before 2030.”
While most of New York City’s waste stream is still dumped in landfills, about 20% is now diverted from landfills, and mandatory organic waste recycling is slowly being implemented. In an interview I did with Renee Cho on the Columbia Climate School’s State of the Planet Blog, I was not particularly encouraged about voluntary or even mandatory recycling. Instead, I argued for a new form of infrastructure to ensure material circularity. As I observed in that interview:
“If we’re going to create a circular economy, we can’t depend on voluntary markets or the voluntary human sorting of waste. We have to set up a system where we have a single line of waste—everything mixed together—and then we’ll use robotics and artificial intelligence to separate the waste electronically, hopefully with renewable energy. This system will be able to mine the waste stream for resources—everything from fertilizer to methane to heavy metals and rare earths and everything else. And the mining operation will pay for the waste separation operation. At that point, mining our garbage will be more cost-effective than mining the planet. The cities that can do this will be much more economically viable than the cities that are still paying to find a place to store and dump their garbage. So I think in the long run, this is going to happen, but I’m talking about a generation from now. It’s not something we’re going to see very soon. But that’s really going to be the future.”
Ironically, the rising cost of transporting and dumping New York City’s huge waste stream provides the revenues needed to pay for a large-scale waste mining and reuse system. We would probably have to build it on an island we construct or occupy in nearby waters with large automated containerized docks for handling waste and recycled materials, since no one will want it in their neighborhood. But a massive recycling facility coupled with increased use of renewable energy would be two pillars of a sustainable New York City that is not difficult to imagine.
In addition to energy and waste, a third key element of a sustainable New York City is improved mass transportation and non-fossil fuel forms of transport. Mobility is key to urban living. Over the past decade, we have seen a dramatic increase in bike lanes and the Citi Bike bike-sharing program. The use of e-bikes and scooters is also rapidly increasing and is in dire need of regulation and policing. We’ve also created dedicated bus lanes to speed bus traffic and developed a functioning, if heavily subsidized, passenger ferry system. With congestion pricing finally established, we have a new dedicated revenue stream that will enable us to modernize our mass transit system. We are starting to build electric vehicle charging stations, and the use of electric vehicles is slowly increasing. The city’s transport system in 2025 looks very different than the one we had at the turn of the century, but the differences were gradual and subtle and a little under the radar.
I think the transition to a sustainable city will be gradual and sometimes difficult to see. As in any transition, the old city sits alongside the new one. Scientists and environmental activists push for rapid change to reduce greenhouse gases, but decarbonization is not the only goal we need to pursue. The homeless need shelter, and working people need affordable housing. Mandatory immediate climate initiatives could raise the cost of housing and must be implemented carefully to avoid negative indirect impacts. As renewable energy and battery storage advance and scale up, their price will go down, and the implementation of green energy will reduce housing costs and facilitate affordable housing. That is why slow and steady wins this race. The circular economy will raise standards of living while reducing environmental damage. It is the future, but not yet the present.
Views and opinions expressed here are those of the authors, and do not necessarily reflect the official position of Columbia School of Professional Studies or Columbia University.
About the Program
The Columbia University M.S. in Sustainability Management program offered by the School of Professional Studies in partnership with the Climate School provides students cutting-edge policy and management tools they can use to help public and private organizations and governments address environmental impacts and risks, pollution control, and remediation to achieve sustainability. The program is customized for working professionals and is offered as both a full- and part-time course of study.
