Ideas for the Sustainable City: Green Buildings

On March 23, the Environmental Protection Agency released a list of the 40 cities with the highest percentage of energy-efficient buildings. While Los Angeles, Washington and San Francisco made the top three, NYC came in at number ten.

When we think about carbon emissions, we often think of cars, trucks, factories, and power plants. We think of towering smokestacks and tailpipes — sources of the fumes we breathe in daily living in an urban environment. Are there really no more poignant Images of air pollution and GHG emissions than an urban landscape masked by smog?

It may come as a surprise to many, then, to know that in NYC buildings contribute to roughly 75% of our greenhouse gas emissions. By law, the city is required to publish a comprehensive inventory of greenhouse gas emissions — and while it is true that NYC is significantly more energy-efficient than the national average (NYC emits 6.4 tons of CO2 per capita, versus the national average of 19.7 tons) — there is always room for improvement as we progress towards a more sustainable future.

In what ways can we “green” our buildings — to make them carbon neutral, for starters, but ultimately to ensure that our buildings give more back to the environment than they take? Indeed, this question is not a pipe dream — for in NYC and across the world there are brilliant and innovative examples of how our buildings can exist in a sustainable harmony with the environment. To quote prof. David Orr of Oberlin College, it possible to “design buildings so well and so carefully that they do not cast a long ecological shadow over the future… [that] promote the practical skills and analytic abilities to reweave the human presence in the world.”

First, we must understand what kinds of emissions buildings ultimately contribute. By PlaNYC’s inventory, 39% of buildings emissions are from residential buildings; 21% from commercial; 8% from industrial; and 8% from institutional buildings. To quote, “the key drivers of these emissions include the types of fuel used for electricity generation; the efficiency of power plants; the size of the spaces inhabited by each person; weather demands on heating and cooling; the efficiency of buildings and workplaces; and personal efficiency measures.”

We have, then, a list of criteria by which the efficiency of buildings might be measured. While the source of power for buildings — mostly coal in NYC — is difficult for the local energy consumer to find alternatives to, building design can reduce the amount of energy required. Some can power themselves, and even contribute back to the grid.

But all green buildings are certified along a spectrum. While the EPA’s index of green cities is oriented towards Energy Star buildings, the green building certification standard is the Leadership in Energy and Environmental Design (LEED) certification. This rating system provides a number of standards by which the design and construction of green buildings may be measured. Buildings may be ranked as Certified, Silver, or Gold — but the highest standard is Platinum.

My first encounter with a green building was Oberlin College’s Adam Joseph Lewis Center for Environmental Studies, a building which meets LEED Platinum certification. The building’s systems are integrative with the site’s landscape — its north side is a soil embankment, meant to insulate the building naturally, and upon which is an apple orchard; the native vegetation is managed ecologically; argon-insulated windows face the south and brick insulates the north side. A solar array both over the parking lot and on the top of the building supplies its power. Its heating and cooling systems are passive. Many of its building materials are sourced locally. Remarkably, the building processes all of its wastewater with a Living Machine, a series of tanks filled with plants and bacteria that clean wastewater which is then returned to the on-site wetland.

For all its lessons and potential, the AJLC is on a rural campus — a campus with lots of space. New York City, and Manhattan in particular, present a different reality and set of challenges for green building design. However, that’s not to say that designers, planners, and architects have not risen to meet the occasion.

As an example of urban green design, the Bank of America Tower represents a landmark in sustainable architecture.  It is the first LEED Platinum Certified skyscraper in the US — an example of how the principles of Oberlin’s AJLC might be applied to an urban setting.  Constructed of locally-sourced and recycled materials, the insulated floor-to-ceiling glass panes to enable passive heating and cooling and provide natural lighting.  It recycles its wastewater and utilizes purifies rainwater for its air conditioning system, and has an on-site cogeneration plant to provide energy.

The Bank of America Tower is not the only Platinum building in NYC. The Queens Botanical Garden was described by the NY Times as “what city officials are calling the ‘greenest’ building ever erected in New York City.”  Like the BoA Tower and the AJLC, it recycles its own water and processes its own waste, but is innovative in using its nearby wetland to process graywater to be returned to the landscape. It has an extensive solar array that will provide 20% of the building’s energy use — proving the feasibility of solar in NYC’s northern latitude.

These buildings, while not comprehensive solutions to the issue of urban ecological sustainability (after all, issues as diverse as stormwater runoff to air quality and ground transportation pollution provide challenges to urban planning and design), they do provide examples of how we might reimagine the way our built environment can not only improve the urban space, but help reduce emissions in mitigating climate change. They are examples of systems thinking that gesture towards reducing building emissions, and ultimately the majority of NYC’s carbon emissions overall.