Behnisch Architekten has completed a dramatic, seven-story building for the University of Pennsylvania: the Vagelos Laboratory for Energy Science and Technology (VLEST)—a LEED Platinum research facility that will house scientists, policymakers and students committed to advancing sustainable energy research.
As the architects explain, “A research facility inherently comes with high energy demands, and one dedicated to sustainable energy research must all the more reflect this mission in its design and operations. A key objective of this project was to design labs and collaborative spaces that embody the principles of the very work being carried out within the building.”
Situated between Walnut and 32nd Streets in West Philadelphia, the project transforms a former parking lot on the eastern edge of the UPenn campus into a pedestrian-oriented space anchored by a glimmering building designed to raise awareness of the critical role that energy research plays in combatting the advancing Climate Crisis.
An angular, energy-efficient envelope designed using EFTE
The envelope of the laboratory has been tailored to solar orientation and employs new materials and engineering designed to optimise energy performance and is completed with ethylene tetrafluoroethylene (ETFE) foil and aluminium. The north-facing facade incorporates more glazing and thin vertical fins, while the south facade features horizontal brise-soleils. The east and west facades are equipped with 267 modular shading elements that are positioned in relation to the sun’s path, allowing for unobstructed views while effectively controlling solar gain. Crafted from 0.2mm double-curved ETFE foil sunshades tensioned on a steel frame, the sunshades are mechanically fastened and fully recyclable at end of life, they reduce the embodied carbon of the facade by approximately 90% in comparison to similar perforated aluminum systems.
Unique spatial organisation for energy efficiency
The spatial organisation of VLEST enhances energy efficiency through the division of the space into two zones: high energy and low energy. This approach allowed the architects to optimise HVAC systems and passive design strategies. Spanning seven floors, the building program includes high-performance labs for chemistry and optics, a nuclear magnetic resonance suite, researcher write-up space, office space and a student clubhouse. Double-height spaces open the structure vertically, alternating between the north and south ends to create a sequence of interconnected terraces, stairs, and kitchenettes along the western facade. The angled eastern facade, which offers views over the Schuylkill River, houses the laboratories.
Passive and active systems reduce consumption
To optimise energy use and to ensure the health and comfort of occupants, the VLEST employs a holistic energy strategy. Central to this approach is the use of passive systems: operable windows allow natural ventilation for up to 30% of the year, taking advantage of the mild climate, while radiant heating and cooling systems in all non-laboratory spaces ensure quiet and comfortable operation.
Active systems have been optimised to reduce consumption. Laboratory air flow rates are minimised without compromising safety, and an automated Aircuity system continuously monitors indoor conditions, adjusting air supply and exhaust based on contaminant levels and thermal load. Heating demand is largely met by repurposing excess reject heat from the heat recovery chiller, while steam condensate is used to pre-heat domestic hot water. The majority of the institution’s heating demand is met by capturing and reusing the waste heat from the building’s cooling system, and steam condensate steam condensate is used to pre-heat domestic hot water.
Ductwork has been minimised to reduce energy loss, and heating and cooling are delivered through water-based systems that operate at low to moderate temperatures. These systems use hydronic-based terminal units—chilled sails, chilled beams and radiant floors—for climate control. Together, these passive and active strategies reduce the building’s overall energy use, acting in support of UPenn’s goal of achieving carbon neutrality by 2042.
Introducing a new biodiverse pedestrian area
The building introduces a new plaza deck, creating a vital pedestrian link between Walnut Street and the Palestra: the university’s historic basketball area. This walkway frames a sunken courtyard alongside the David Rittenhouse Laboratory and extends westward to connect with Shoemaker Green. The plaza’s arms define a new courtyard, transforming what was once a parking and delivery area into a verdant space completed with bio-retention swathes and native planting. Three bio-infiltration basins collect and recharge groundwater to manage stormwater runoff. The building is connected to a cycling network and provides 36 onsite parking spaces for bicycles.
