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The Center for Sustainable Landscapes at Pittsburgh’s Phipps Conservatory and Botanical Gardens strives to generate all the energy it needs to operate. Being dubbed the future of green, this building is entirely sustainable, with solar-, wind- and geothermal-generated power; lighting and HVAC automation; and a water filtration system.
Hanlon Electric Co. provided primary electrical construction for the project, working with general contractor Turner Construction. The work helped make this building—reportedly the greenest conservatory in the world—a reality.
For more than a century, the Phipps Conservatory has showcased gardens with plants and trees from around the globe and has been a leader in the botanical arena conservation. However, Phipps was established at a time when energy consumption was no great concern. A century later, exotic plants are still showcased, and the conservatory tries to help people connect with nature as it is, without creating an energy footprint, said Richard Piacentini, Phipps’ executive director.
Hanlon Electric has its own long history in the Pittsburgh area. The company was founded in 1930, with a major focus on schools, colleges and other public institutions. Hanlon Electric’s relationship with Phipps dates back two decades; the Monroeville, Pa., company has provided electrical installation of a three-phase plan to improve the conservatory’s facilities.
In 1999, the conservatory owners first got interested in Leadership in Energy and Environmental Design (LEED) construction. It took on three LEED landmark projects with Turner Construction and Hanlon Electric, including a new welcome center. With the recent showcase of the $20 million three-phase project, however, the Phipps leaders wanted to do more than mount a LEED plaque at the building entrance; they wanted to be entirely sustainable. The result is the 20,000-square-foot Center for Sustainable Landscapes (CSL), which is expected to produce more energy—through alternative sources—than it uses from the utility.
“When we first decided to do this, we wanted to speak about the talent in Pittsburgh, so we started the process of putting together a local team,” Piacentini said.
The conservatory hired Turner, which, in turn, brought in Hanlon Electric. The key to the project’s success, according to Piacentini, was to use an integrated design approach. Participants spent months in meetings reviewing construction plans.
The CSL is perched on a bluff and is surrounded by native trees outside, while housing a variety of tree species inside. The presence of both creates some challenges. The numerous native trees are vulnerable to wind and can knock down power lines, while the trees inside, in some cases, wouldn’t survive long without the power that keeps them heated in the cold, frosty Pittsburgh winters. Therefore, the building needs a way to keep power operating full time.
“Having emergency power is pretty critical,” Piacentini said.
So the conservatory, working with the project team, spent several years developing plans for a sustainable design that would provide reliable, uninterruptible power.
The resulting building includes a passive solar design and geothermal heating and cooling.
GEOTHERMAL
As part of the power generation, the building includes 14 geothermal wells of 500-foot-deep boreholes.
The building is expected to acquire about 70 percent of its heating and cooling energy from the earth. A rooftop energy-recovery unit uses ground-source geothermal energy to provide further heating, cooling, ventilation and dehumidification. A desiccant energy-recovery wheel precools and dehumidifies outside air, which reduces the cooling loads of hot, moist outside air in the summer. In the winter, it can preheat and humidify dry, cold air.
SOLAR
Hanlon Electric installed the power distribution for a 125.75-kilowatt (kW) solar array in three locations: one on the ground and two on the building roofs. The solar panels provide electricity to the building, and excess generated energy is used to serve the upper campus as needed, said Michael Hanlon, company president and CEO. Pittsburgh Solar Energy Independent Solutions installed the panels. The array consists of 501 solar panels of 250 watts each, covering 9,000 square feet.
The resulting system produces an estimate of 137 kilowatt-hours per year, while the building is anticipated to use 125 kW per year. The panels provide enough power to energize 10 typical American homes.
Some changes were made along the way. Early on, the design team opted to bring the solar-power system online ahead of the CSL building. Hanlon Electric collaborated with the construction team on a design change to feed the solar panels from the existing special events building rather than through the CSL building and out of the ground, as in the original plan. This allowed the CSL building’s original 600-ampere (A) feed to be split into two 300A feeds—one for CSL’s normal power and another for standby power. This allows the CSL building and the entire Phipps campus to function independently of utility power, indefinitely, in case of emergency.
In addition, the solar array provides more power than is expected to be used in the CSL building, but it is designed to accommodate degradation of the panels that is typical over the course of several years, Hanlon said.
WIND
Hanlon Electric was also responsible for tying in a 10-kW vertical axis wind turbine (VAWT), which also provides power to the building. While a larger wind generator was possible, the low-profile VAWT was selected so as not to detract from the appearance of the historic 100-year-old greenhouses. Any excess power provided by the turbine also is sent back to the grid.
LIGHTING CONTROLS
The building is designed to maximize the use of natural light and air flow, using a window system that opens and closes automatically depending on outside conditions.
To further increase the energy efficiency, the facility had an extensive building management system installed that includes a direct digital control to monitor and manage the energy systems and provide feedback about them. It includes a Lutron Electronics Co. dimming system for lighting and a notification system to alert building occupants if temperature, air quality conditions or humidity seem to necessitate opening windows.
In addition, when outdoor temperatures are measured to be favorable, the system starts a “night purge” in which cool dry outside air is pumped through the building to save on daytime cooling energy consumption.
The upper windows open automatically when the conditions require it; however, building staff are expected to open the lower windows themselves.
“We find the simple act of requiring people to open windows get them engaged [with the outside world],” Piacentini said.
The building control system software alerts staff, through desktop notification, when the time is right to open those windows. Hanlon Electric provided the power to the automatic windows and sensors that detect condition data used by the control system, said Terrence Hanlon, project manager.
The daylight sensors are designed so that those lighting fixtures closest to the southern sun exposure are dimmer than those in portions of the building that fall in shadow. Each lighting fixture Hanlon Electric installed is addressable, enabling users to control and dim each one. The system also allows for occupancy control and emergency egress lighting.
In the future, this Lutron Quantum system is capable of interfacing with the public utility, Duquesne Light, so that, in the event of power shortages, the utility can request the Lutron system to shed some of the power load. All lamps are energy-efficient LED and fluorescent technology.
WATER
Hanlon Electric also ran cable for an electrical system to pump water through a complex water management and filtration solution. Using a rainwater-harvesting system, a lagoon collects overflow water and routes it to underground rain tanks and on to a series of cisterns. It is then used to water plants in the conservatory.
Wetland sand filters also were constructed to clean water from the CSL building and adjacent maintenance building, which is then pumped to a tank to be reused for toilets.
The water system also includes an Epiphany System, which allows Phipps to distill some of its water for specialized plant watering needs—such as water-sensitive orchids—in its greenhouses.
SUSTAINABLE PRODUCTS
This project had strict sustainability rules for products used in the electrical construction. Even the vehicles used in the project had to meet emissions requirements to be used on-site.
All the building’s own materials and tools used for construction had to meet sustainability requirements. When possible, Hanlon Electric was also required to use locally produced material with low volatile organic compounds (VOC) and low formaldehyde toxicity. Wood was salvaged from western Pennsylvania barns.
For Hanlon Electric, obtaining the most sustainable products required time and patience. The project called for contractors to submit product data for every item installed, which was a monumental task requiring cooperation from manufacturers, who were often reluctant to guarantee in writing that their product did not contain any of the “red listed materials.”
In some cases, the contractor worked with manufacturers that had never been asked about the materials in their products and were either unable or unwilling to share that information.
“As the submittal process took time, we had to preplan every task and identify every part required far in advance,” to ensure the right product would be approved and available when needed, Michael Hanlon said.
The products also needed to be properly protected, such as having coatings to prevent any possible corrosion. Products such as Neoprene, commonly employed by cable manufacturers, could not be used.
Piacentini said many manufacturers asked themselves for the first time what materials they use and whether they should change those materials to be more competitive for green building.
“It was an important process; it starts getting manufacturers thinking about what’s in their products,” he said.
Altogether, Hanlon Electric ran about 30,000 feet of Cat 6 cable for more than 300 drops in the CSL building. The final part of the project was installing electric vehicle fueling stations.
The Phipps Conservatory isn’t the only sustainable aspect; the relationship is another.
“I think what I’m most proud of is our continuing relationship with Phipps,” Michael Hanlon said.
About The Author
SWEDBERG is a freelance writer based in western Washington. She can be reached at [email protected].