The Green Skyscraper
- October 10, 2010
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This is a guest post by Joshua Rinaldi, a first year doctoral student in the McCormack School of Public Policy and Global Studies at the University of Massachusetts, Boston.
Massive monolithic figures that cut across horizons, skyscrapers have been symbols of a city’s wealth, prosperity, and architectural ingenuity since their inception. Now, some skyscrapers are taking on another symbolic venture: a green one. New York City is home to one of the most sustainable skyscrapers in the world. The Bank of America Tower is 1,200 feet of green architecture at its finest. The second tallest building in New York City earned LEED “platinum” status in May 2010 as testament to its energy efficiency, and was the first skyscraper to receive platinum status. The $1 billion tower comes with a gray-water system that captures and re-uses rain and waste water that saves 10.3 million gallons of water annually, a crystalline design that allows for maximum use of daylight, and an onsite 4.6-megawatt generator that provides an efficient, clean power source for part of the building’s energy needs. However, energy efficiency isn’t limited to new, green skyscrapers. Some of the tallest skyscrapers in the United States are now aiming also to become some of the greenest.
In April 2009, New York City Mayor Mike Bloomberg announced plans to invest $20 million to make the 79-year-old Empire State Building, which was the first building in the world to top 100 stories, more energy efficient. With the installation of 6,500 energy-efficient windows, extra installation around radiators, and a more efficient lighting system, the improvements are expected to save the building’s owners $4.4 million annually in energy costs when renovations are complete in 2013. The renovations are also expected to reduce the building’s carbon emissions by 105,000 tons in the next 15 years. In April 2010, the John Hancock Tower in Boston was given gold certification by the U.S. Green Building Council for instituting measures to cut water use and carbon emissions.
Almost 800 miles to the west, the owners of the tallest skyscraper in the United States were also lining up to go green. Owners of the Willis Tower (formerly the Sears Tower), announced plans to invest $350 million dollars to renovate the 36-year-old tower. The 5-year plan will require upgrades to the lighting system and the replacement of more than 16,000 single-pane windows. The building will add solar power and, possibly, wind power, which is expected to provide all energy needs for an adjacent hotel project. Architects had considered changing the building’s trademark black exterior, which attracts heat, with more energy-efficient silver, but such plans have since been discarded.
The aforementioned buildings are just the most well-known examples. The Skyscraper Museum cites 15 buildings that form a “new class” of sustainable skyscrapers in New York City. That class includes the New York Times Building, the Hearst Tower, and the Freedom Tower that will eventually be built on the World Trade Center site. Other cities are greening skyscrapers as well. The owners of the Christman building in Lansing, Michigan recently spent $8.5 million to green the 81-year-old historic building.
The rush to go green
With a credit crunch and one of the worst construction markets in decades, it seems like an odd time for an explosion of green renovation. One of the main reasons is that buildings need tenants in this uncertain market, and a green LEED certification makes the building more attractive. Real estate researcher CoStar Group, Inc. performed an analysis that found that green-certified buildings had fewer vacancies than other similar sized buildings and had $2.05 per square foot rental premium over their non-LEED counterparts. Additionally, the report said that LEED certification has shifted from new buildings to existing building. Existing buildings made up just 15 percent of LEED-EB certifications in 2008 but is up to 35 percent in the first quarter of 2010. This is not surprising because evidence suggests that green buildings sell or lease better, retain tenants better, and often have more productive tenants than similar non-green buildings.[i]
Renovation projects aimed at greening skyscrapers almost universally include energy-efficient windows and efforts to install lighting that is energy efficient. For instance, some buildings set the lighting to dim automatically when not needed. Most skyscrapers have flat roofs, which provide the potential for solar power. On a city-scale, this could provide quite a boost to the electrical grid. The Willis Tower is expected to include this approach as it moves toward sustainability, but the Empire State Building, with its antenna roof, does not.
The possibility of more energy-efficient skyscrapers bodes well when considering the energy costs associated with buildings. In New York City, greenhouse gas emissions from its 900,000 buildings, more than 5,000 of them classified as skyscrapers, constitute almost 80 percent of the city’s carbon footprint. In addition to lowering emissions, green buildings consume less energy, which would lower demand on the grid, greenhouse gas emissions, and local pollution.
It also makes good business sense. Renovation costs, which can total tens of millions of dollars, will be recouped via energy savings and possibly water savings depending on the upgrades. The Empire State Building owners expect energy savings of $4.4 million annually. The brown water system in the Bank of America Tower saves millions of gallons of water every year, which also results in cost savings. The federal stimulus package alone had $4.5 billion in green building grants. This is in addition to an energy-efficient federal tax deduction that could total up to $1.80 per square foot in commercial buildings. States generally offer incentives as well. As Amory B. Lovins said in a New York Times editorial, “Efficiency can save 75 percent of America’s electricity at lower cost than making it at existing power plants. Helping customers reduce or defer usage when electricity is scarce can also increase distribution equipment’s life and reliability.” Customers who reduce power use at peak times can also negotiate lower rates with utilities.
While energy efficiency and tax deductions can usually pay back the costs of renovations there are still barriers to retrofitting skyscrapers, especially famous ones like the Empire State Building or Willis Tower. The most direct obstacle is the bureaucracy of city planning commissions and various zoning or preservation boards. The Empire State Building is a New York City landmark, which means the New York City Landmarks Preservation Commission will have to approve the plans for the retrofit to the exterior and ground floors of the building.
Bureaucracy isn’t the only barrier. Environmentalists and preservations may find themselves at odds if a historic building’s appearance is changed in the name of energy efficiency. As a blogger for the Chicago Tribune noted regarding the proposed changes to the Sears Tower’s trademark black facade, “Sears is not yet a historic landmark, of course, but the very idea that its iconic image could be radically altered in the name of environmentalism sent shockwaves coursing throughout Chicago’s architectural community.” While this doesn’t guarantee an adverse reaction to a greening of landmark buildings, it indicates that many people are reluctant to alter the icons that define their city.
Another potential barrier could be the amount of time it takes to see cost savings from renovations. A recent report by the Department of Energy shows that while carbon reduction is still high, cost-savings of green renovation can vary wildly by city. A computer model projected identical energy-efficiency improvements for imaginary four-story commercial buildings in Chicago, Baltimore, and Newport Beach, Calif. The computer found the improvements had the greatest effect in windy Chicago with a 23 percent energy reduction, which would pay for itself in nine years. Projections for Newport Beach and Baltimore showed lower reductions and estimated that it would take at least 11 years to pay off via energy savings. Environmentalists dispute the study as flawed and argue that there is more research that demonstrates energy savings. But the uncertainty regarding return on investment, partly due to unknown future energy prices, is often cited as a major barrier to investment.
A solution to this dilemma presents itself in the book Natural Capitalism. The authors contend that direct energy savings are only a portion of the equation. Claiming that energy-efficient buildings provide better lighting, improved air quality and a more comfortable environment, the authors argue that building owners also will see savings from increased productivity, reduced absenteeism, and increased occupancy.[ii]Such savings or gains are difficult to quantify, but could be used to sway hesitant business owners. Case studies that document the financial effects of such outcomes may be the most effective way to demonstrate such results in the absence of a savings model for the methods.
Expanding the green skyscraper movement
As President Bill Clinton noted at the announcement of the Empire State Building’s plans, “We have to prove it’s good economics, and we have to prove we know how to do it. Every person on Earth who cares about this knows about the Empire State Building.” The same could be said about Willis Tower. So despite some obstacles, the fact that the tallest and most famous skyscrapers in the United States are striving for energy efficiency may do wonders to encourage other investors to follow suit.
Market pressures in a depressed economy may encourage property owners to make the investment. The Associated Press reports that one of the Empire State Buildings’ incentives was to fill vacant office space. As the article says “Many high-profile tenants won’t even consider moving into a property without the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) certification…They may not even know what the certification means, but they demand it nonetheless.” If the public continues to become more energy conscientious, owners may take steps to cater to them.
In the United States as a whole, buildings account for 38 percent of greenhouse gas emissions and that number jumps to almost 80 percent in a city like New York. As the Bank of America Tower indicates, architects are interested in designing energy efficient buildings and companies are interested in those buildings. Nevertheless, it is still important to note that the greenest building is one that is already built. As New York City’s PlaNYC 2030 estimates, 85 percent of the buildings that will be in New York City in 2030 already exist now. Other major cities are likely to retain old buildings at a similar rate. As New York City Mayor Bloomberg said, “Existing buildings, no matter how tall they are, no matter how old they are, can take steps to significantly reduce their energy consumption.” If a city is going to significantly reduce its carbon footprint, its skyscrapers will have to do just that.
[i] Paul Hawken. Natural Capitalism : Creating the Next Industrial Revolution. Ed. Amory B. Lovins and L. Hunter Lovins. Boston: Boston : Little, Brown and Co, 2000.