In 2019, the City Council enacted a package of bills to reduce the greenhouse gas emissions that cause climate change, including one bill that became Local Law 97 and set limits for emissions from large buildings. Building owners are scrambling to figure out how to pay for upgrades to comply. I asked our writer Jane Margolies to explain. There’s a series of deadlines. You wrote that nearly all of the 50,000 buildings subject to this law will meet the first one, in 2024. What about the second deadline, in 2030? How hard will it be for building owners to comply with the standards that take effect then? What kind of work will they have to do? It’s going to be much, much harder to meet the standards in 2030. For 2024, most buildings that are running reasonably efficiently — buildings that are well insulated, have LED lighting, have heating systems tuned up and don’t have old, rattly, single-pane windows — are going to hit the standards. It’s pretty low-hanging fruit. For 2030, it could t