Today, on the day of the People's Climate March, Mayor Bill de Blasio announced a plan for NYC to reduce greenhouse gas emissions by 80% (over 2005 levels) by 2050, starting with huge efforts to improve the energy efficiency of public and private buildings. De Blasio said, "Climate change is an existential threat to New Yorkers and our planet. Acting now is nothing short of a moral imperative."

De Blasio added, "New York City must continue to set the pace and provide the bold leadership that’s needed—and becoming the world’s largest city to commit to an 80 percent reduction in emissions by 2050 is central to that commitment. By retrofitting all of our public buildings with significant energy use in the next ten years, we’re leading by example; and by partnering with the private sector, we’ll reduce emissions and improve efficiency while generating billions in savings and creating thousands of jobs for New Yorkers who need it most."

The plan is called One City, Built to Last: Transforming New York City’s Buildings for a Low-Carbon Future, and the mayor's press release includes these notes:

Nearly three quarters of New York City’s greenhouse gas emissions come from energy used to heat, cool, and power buildings, making building retrofits a central component of any plan to dramatically reduce emissions. The City is poised to make direct investments to increase the efficiency of its public buildings, including schools and public housing, reducing the government’s contribution to climate change and generating operational savings for New York City taxpayers. Every single city-owned building with any significant energy use - approximately 3,000 buildings - will be retrofitted within the next ten years, by 2025, with interim goals along the way. The City will also spur private building owners to invest in efficiency upgrades, setting ambitious interim targets and incentives to catalyze voluntary reductions, and implementing mandates that trigger if interim reduction targets are not met - leading to retrofits in tens of thousands of private-owned buildings. High energy costs take a disproportionate toll on lower-income residents who typically live in less-efficient buildings and must pay a higher share of their income for energy. The City’s plan aims to protect New Yorkers from rising utility bills while reducing emissions and poor air quality and stimulating demand for retrofitting and renewable energy jobs This plan is projected to reduce greenhouse gas emissions by an additional 3.4 million metric tons a year by 2025 - an additional 10 percent reduction in building-based greenhouse gas emissions, equivalent to taking 715,000 vehicles off of the road. This will also generate cost-savings across the public and private sectors of more than $1.4 billion a year by 2025, leading to $8.5 billion in cumulative energy cost-savings over ten years. It’s anticipated that approximately 3,500 new jobs in construction and energy services will be created, in addition to the training of more than 7,000 building staff to upgrade their skills.

According to the NY Times (which points out that the plan is being "announced before the start of the United Nations Climate Summit on Tuesday), "Such ambitions, though, will come at a significant near-term price: At least $1 billion of its capital funding alone will be devoted to enhancing the city-owned buildings over the next decade, the administration said, excluding the cost of the private building alterations and other changes. Though the city’s many competing financial interests mean there are typically few spending guarantees, particularly on projects intended to span decades, officials insist the money will be incorporated in its 10-year capital plan, to be released early next year." On the other hand, the projected cost savings!

And some environmental groups told the Times that the plan was pretty good, with the Natural Resources Defense Council's saying it "could be the most far-reaching one of its kind."