A biotechnology company has added a six-story net-zero building to its downtown campus in Silver Spring, Maryland.
Designed by EwingCole, the 19,510-m² (210,000-sf), elliptical shaped Unisphere is one of the largest net-zero buildings in the country. It houses clinical operations for pulmonary disease, heart failure, and organ transplantation as well as a virtual drug development lab.
“This smart building takes advantage of multiple sustainability strategies,” said Jared Loos, PE, AIA, EwingCole CEO. “It has no operational carbon footprint because the electrical and thermal energy is renewably generated onsite. It is truly an engineering marvel.”
Strategies employed to achieve net-zero status include the following:
- 3000 solar or photovoltaic (pv) panels on the building generating 1175 mWh of energy each year, enough to power 100 homes.
- A quarter-mile-long concrete maze is located 4 m (12 ft) below the Unisphere. This natural ventilation system, moderates temperatures within the atrium as compared to the exterior climate.
- Beneath the Unisphere, 52 closed-loop, dual-circuited geo-exchange wells are drilled 152 m (500 ft) into the earth to provide energy storage.
- The atrium pool is used as a heat sink to help balance the overall system and provide passive heating of pool water.
- Daylight harvesting allows dimming of the artificial lighting system when adequate sunlight is available.
- The office area windows use electrochromic glass technology that changes tint level based on season, location of the sun, and cloud coverage.
- Operable windows and panels allow the building to naturally ventilate, thereby providing a completely passive ventilation mode between certain temperatures.
- Excess power is sent back into the utility grid during peak production times, and the utility grid supplies this power back at night and at off-peak times.