By Jenny Jones
A new elementary school in New York City will be fitted with photovoltaics and numerous energy-saving systems to become the first net-zero elementary school in the state of New York.
Located on Staten Island, the first net-zero elementary school in the state of New York will be outfitted with more than 2,000 photovoltaic panels to produce 730,000 kWh of electricity annually. © SOM
July 22, 2014—A new 68,680 sq ft primary school near the south shore of the borough of Staten Island, in New York City, will be the first net-zero energy elementary school in the state of New York. To achieve energy neutrality—harvesting as much renewable energy as it uses annually—nearly every aspect of the building's design is dedicated to either producing energy or reducing energy consumption.
P.S. 62 Richmond, as the new school is known, is the culmination of efforts by the New York City School Construction Authority (SCA) to make the city's schools as energy efficient as possible. Responsible for managing the design, construction, and renovation of the city's more than 1,200 schools, the SCA created the NYC Green Schools Guidein 2005 after the city passed Local Law 86, which outlines stringent sustainability requirements for city-funded projects. The SCA has since been making the city's schools progressively more sustainable by incorporating such elements as natural daylight and highly efficient heating, ventilating, and cooling systems into the school buildings.
But when the SCA received an assignment to construct a new elementary school on a three-acre site on Staten Island, it saw a chance to take its sustainability efforts to an even higher level: net zero. To achieve net zero, a building must have an energy-producing system. And unlike some other New York City locations, the Staten Island site provides the unusual opportunity to produce energy with photovoltaic (PV) panels because it is surrounded by low-rise buildings. "The low-scale neighborhood [will] maximize the full-day generation by PV panels—unlike a more [high-rise] urban location where roofs might be shaded," explains Bruce Barrett, LEED-AP BD+C, AIA, the SCA's vice president of architecture and engineering. "This seemed like a great opportunity to achieve net zero, and when we talked to our president, the mayor's office, and other city leaders, everyone was very enthusiastic about it."
The school will have numerous strategically placed windows, skylights, and sloped ceilings to direct sunlight into the interior spaces. Natural light will provide 90 percent of the school’s lighting needs during daylight hours. © SOM
The SCA launched a public procurement process for the project in 2011. Given the rapid and ongoing advancements in sustainable technologies, the authority structured the contract documents in a way that allowed for changes in certain specified technologies during the project's construction. For instance, the SCA did not request light-emitting diode (LED) lighting in classrooms in the 2011 bid set because the technology did not perform as well in classrooms as the more commonly used fluorescent lighting fixtures at that time. But LED technology was improving so quickly that the SCA suspected that it might be ready for classroom use some time after construction commenced. That prediction proved accurate: P.S. 62 Richmond will be the first New York City school with LED lighting throughout, Barrett says.
As a result of the public procurement process, the SCA selected the New York City office of the multidisciplinary firm Skidmore, Ownings & Merrill (SOM) to lead the project design. The firm is responsible for the architectural, interior, and sustainable systems design. Subconsultants to SOM include DeSimone Consulting Engineers, a New York City-based firm that is serving as the structural engineer on the project, and In Posse, a Philadelphia-based engineering firm that is the serving as the sustainability engineer on the project. DeMatteis Construction Group, a firm based in Elmont, New York, is the project's general contractor.
In keeping with the milieu of the Staten Island neighborhood, it was clear that the school would have just two levels arranged around a central courtyard. But Jon Cicconi, AIA, the senior design architect on the project and an associate with SOM, says that prior to developing detailed plans, the design team had to conduct a significant amount of research to determine how much energy the school would likely use. Teachers and staff had not yet been assigned to the new school, so the team interviewed those from other schools about energy consumption in a typical New York City school. "We had to consider every aspect of the use of the building, so we talked to far more people about the design than we would for a typical project," Cicconi says. "The greatest challenge was trying to predict the future energy use."
The rooftop photovoltaic panels will be supported by steel outriggers that are designed to maximize the roof space and expose the panels more directly to the sun. © SOM
The team learned that the cafeteria is one of the biggest energy users in a New York City school. The kitchen equipment in a typical cafeteria takes a great deal of time to heat up, so the chefs usually leave it on from breakfast through lunch, which draws a lot of energy. To prevent that from happening at the new school, the kitchen equipment will be highly efficient and heat up rapidly. "That change alone saved almost 20 percent of the entire building's energy use," Cicconi says, adding that SOM's design will provide 50 percent less energy consumption than a typical New York City school.
The team also learned that teachers often have coffee pots, small refrigerators, and other appliances in their classrooms that add to a building's overall energy use. To encourage teachers to leave those appliances at home, the team made it a priority to design inviting teachers' lounges. The lounges will be spacious, filled with natural light, and connect directly with outdoor patios. "Teachers' lounges in public schools are kind of the last thing designed, and they're usually not well thought out," Cicconi says. "We invested a lot of time and energy into making a very nice teachers' lounge on both floors of the building that people will want to use."
The school's other energy-saving features will include 81 geothermal wells drilled to a depth of 425 ft for efficient cooling and heating. It will also have numerous strategically placed windows and skylights, sloped reflective ceilings, and direct daylight and glare-control features, which combined will provide the building with 90 percent of its lighting during the day, Barrett notes.
One of the school's most unusual energy-saving elements will be its extensive demand-control ventilation system. The SCA has used such systems in gymnasiums and cafeterias in the past, but never in classrooms. This system will have small air intake ports in each classroom to detect carbon dioxide in the air. When the gas is detected, the system will know that people are in the room and automatically provide adequate ventilation. "It is a system that we will prove out in this school to see whether we should incorporate it into future projects," Barrett says.
As it reduced the building's energy use, the design team used energy models to calculate how much energy the building must produce to achieve net zero. Unlike most net-zero schools across the country, this school will operate at least 12 hours a day, nearly every day of the year, making it more difficult to achieve energy neutrality. As a result, the school will have more than 2,000 PV units producing an estimated 730,000 kWh of electricity each year.
The PV units will cover the school's expansive roof, its two south-facing facades—a product of the school's courtyard arrangement—and a canopy that will cover the parking lot. Sloped steel outriggers will support some of the rooftop units to maximize the space and expose the panels more directly to the sun. While the PV units will produce a significant amount of energy, they will not have a payback during their useful life because the New York Department of Education pays a discounted rate for electricity, Barrett says.
Minimizing air and water penetration was also key to achieving the net-zero status. The steel-framed structure will be wrapped in a multilayered envelope: steel studs, waterproof sheathing, an air vapor barrier, and 4 in. of rigid insulation. "After that, a two-inch air gap and a rain screen of precast concrete panels, supported from the roof and at the base of the building, will complete the facade," says Aileen delPrado, P.E., LEED-AP BD+C, the director of capacity projects for the SCA's Design Consultant Management Studio. A full-scale mock-up of an exterior wall section was constructed and tested in a laboratory to ensure that the envelope would perform as anticipated. The contractor is performing air- and water-infiltration tests on the actual building as it is being constructed on site. A double-slab roof will provide additional protection against air and water penetration and also serve as a foundation for the PV units' supporting structure.
All of the school's energy consumption and production will be monitored via an energy management system; electronic dashboards located throughout the building will indicate how and where energy is being consumed. "Occupant engagement is absolutely critical for the success of any net-zero project," delPrado notes. "We want to engage all of the occupants in the building, whether they be students or teachers, to reduce energy usage as much as possible." Monitoring the energy use is also important because the school will serve as "sustainability lab" for the SCA. "Even if we can't do a net-zero school again, we want to know what components we might want to use on projects in the future," Barrett explains. "This is a wonderful opportunity for New York City, and certainly for all of us who have worked on the project, to have a milestone project that will be the first of its kind in the state."
The award-based budget of the school was $70 million. Barrett says that when the cost of the PV units is subtracted, the school's price tag will be approximately 10 percent more than a typical New York City school. "We were pleasantly surprised that these systems and components that we selected because of their energy efficiency actually added very little cost premium to the building," she says. Construction is under way, and completion is anticipated in the fall of 2015, when the school will open with capacity for 444 students.