A report by the Urban Green Council makes the case that the country’s largest population centers can reduce their carbon footprint 90% without new technology.
Specifically, the 51-page report, titled “90 by 50,” finds that New York City could slash its emissions by a whopping 90 percent by 2050 without any radical new technologies, without cutting back on creature comforts, and maybe even without breaking its budget.
That’s a far more aggressive target than even the city’s own relatively ambitious goal of reducing emissions by 30 percent by 2030. How is it possible? The strategy has plenty of familiar components—electrifying the transit system, converting to renewable power sources. But it all hinges on one seemingly mundane yet surprisingly potent move: retrofitting almost every building in the city to keep the heat in during the winter and out during the summer. In a nod to Rudy Giuliani, Bill Bratton, and James Q. Wilson, I’ll call it the “triple-pane windows theory” of greenhouse-gas reduction.
The report takes as its starting point this foundational statistic: 75 percent of the readily measured carbon emissions in New York City come from buildings.
The key, says the Urban Green Council’s executive director, Russell Unger, is that the city must begin to view buildings as infrastructure, like roads and sewers, rather than simply as private property. “It will require a mind shift for the public and the government,” Unger says. “But you know, most of these buildings will last longer than the Tappan Zee Bridge.” And they gobble carbon-fueled energy like crazy. To get those emissions under control will require three main steps, all difficult but none inconceivable. The first is probably the most ambitious and innovative: gradually retiring the city’s massive, aging steam heat system and replacing it with high-efficiency electric heat pumps. Low-rise residential buildings would get individual mini-split pumps, a relatively easy fix, while high-rises would need to convert from steam to central geothermal heat pump systems. That’s an expensive proposition, but it would also save staggering amounts of energy over time, with cost savings that would help offset the capital outlay. And the retrofits wouldn’t happen all at once—they’d be done as each building comes in for renovations that it would need anyway.
Heating the city’s buildings and water electrically would make it far easier to draw that energy from renewable sources.
It’s the third step, though, that may make the above possible: energy conservation. Here, the report isn’t asking residents to cut back—it refers to stripping waste and leakage to the bare minimum. Tweaks that seem small—insulation, plugging air leaks, heat-recovery ventilation, fluorescent lighting—loom big.
... not just double-glazed windows, but triple-glazed windows—and apply ... to existing buildings as well whenever they’re updated.
This sounds great in theory. When one of our windows broke and couldn't simply be reglazed, we looked into the best recommended energy saving low-e replacement options in 2010. We wanted to go triple pane because of the greater efficiency, but the cost was prohibitive. For a double pane low-e replacement window installed we shelled out $1,531.77.
High efficiency spray foam insulation, on the other hand, makes a serious difference compared to fiberglass insulation. When a mold problem forced us to strip our sun room down to the shell and redo the entire interior, the new spray foam dramatically improved its warmth in cold weather. Of course it too cost an arm and a leg, with specialized installers wearing protective gear.
I often wondered why heat recovery ventilation isn't standard building practice.
All in all this is a far more attractive than keeping the thermostat low in Winter and high in Summer.