The greatest barrier to making real progress on climate change may not be the oil lobby, overconsumption, or a lack of technology: it’s the widespread dread that nothing can be done.
That’s the message of “90 By 50” a recently released report from the New York City-based Urban Green Council that examines how its hometown could reduce its carbon footprint by 90% (!) between today and 2050 using widely available technologies.
While New York City is already working toward a goal to reduce emissions 30% by 2030, Urban Green Council calls those initiatives “noble and largely successful” but essentially, underachieving. Climate scientists agree that we need to reduce emissions 80% by 2050 to keep climate change from permanently spiraling out control.
Building and tinkering with a virtual model of New York City, the researchers behind the report found that it’s not getting cars off the road or putting stricter restrictions on factories that will likely get the most savings in New York. What New York needs to do is make the city’s buildings— which account for 75% of greenhouse gas emissions—more energy efficient.
Russell Unger and Richard Leigh, Urban Green Council’s executive director and research director, respectively, walked me through some of the suggestions in the reports, which focuses on the often less-than-sexy, practical ways that building owners could reduce carbon emissions, starting today.
New York City’s older buildings are like a leaky sink for air. In the winter, cold air blows in through the front door, sweeps through the hallways, and drives warmth out of the apartments. Leigh says the very first thing that every building owner should do to lower its demand for energy is to make the building airtight (similar to the strategy of the "passive houses" I’ve written about before.)
This includes caulking electrical outlets, tightening up loose windows, adding weather stripping to the front doors, and sealing elevator houses on the roofs. Unger says this is actually “one of the toughest things to get right—not as a code issue but a practice issue” since it involves paying much more attention to airflow, which property managers and handymen aren’t used to.
“If you have been very successful with your air sealing […] then you may have made the building so tight that you don’t have enough fresh air,” says Unger. Step 2 is a remedy to that—by installing an artificial ventilation system for heat recovery. This will simultaneously push out stale, warm air from the building and use the warm air to slightly heat the cold but fresh air that enters from outside.
Sure, there are modest energy savings, but this step is mostly about preserving a healthy indoor environment, free of moisture, mold, and carbon monoxide.
Triple-glazed windows with wood or fiberglass frames may cost more, but “the modest extra cost will get paid back in fuel savings,” says Leigh. The report suggest that every window, when its time has come, should be replaced with the best quality window possible.
Unger and Leigh admit that adding insulation can be one of the trickier recommendations on the list since it’s more of a construction project. Low-hanging fruit include spots under the rafters or under the roof, where insulation can be easily tucked away. They also suggest using weatherproofed foam insulation on top of a roof membrane or even on “ugly walls on the backside of your building” says Leigh.
Insulation is currently improving all the time. Recently developed (and, for now, more expensive) types can be as effective with one inch of thickness as seven inches of what you’ll currently find at Home Depot. Who knows what we’ll have available by 2050.
Sunshades above windows help keep out the sun in the summer, which means less need for AC. The energy savings won’t be quite as significant as the other steps mentioned here, but will certainly make a difference (especially if implemented across the whole city).
While steps 1 through 5 would significantly decrease the overall demand for energy of the city’s building stock, steps 6 and 7 would transition buildings away from oil and gas for heat, toward electricity (which, in the future, will come from more renewable sources) and solar power.
Mini-split heat pumps—which can heat or cool a building year round with electricity as the only energy source—are tremendously popular in Japan, but have only been available in the States for the past decade or so.
They work similar to an air-conditioning unit—pushing the hot air out of the building in the summer (but then doing the same for the cold air in the winter)—and would replace the city’s old-fashioned steam system.
Of course, installing one of these means using way more electricity. The report anticipates that the city’s power supply will increasingly move toward renewables and away from coal over the next four decades. And it also assumes that the pump is operating in a house where steps 1 through 5 have been accomplished (which results in a greatly decreased demand for energy.)
It may come as a surprise to see rooftop solar panels as the last step on this list—renewables are often optimistically framed as such a crucial answer to climate change—but Unger and Leigh included them as a coda: Once the other steps are taken to reduce demand for energy, buildings should attempt to create their own energy by adding solar panels.
Unger and Leigh explain that the suggestions are not meant to serve as a specific policy program; instead, they’ve been crafted in a political vacuum to show that there is, at least, a way to do something about climate change (and the full report gets into other carbon savings to be had from the waste and transit sectors).
"One of our hopes for the study is that we’ve helped paint a sense of what we want to get towards," says Unger.