Smart, Eco-Friendly Technology Campus

Uber Technologies (Uber) is an emerging technology giant on a mission to set the world in motion. By providing safe, reliable transportation to customers everywhere, cities across the planet are becoming less congested and gradually safer. In Uber’s vibrant home city of San Francisco, the construction of its headquarters is looming; the two towers, Mission Bay 1 and 2, exceeding 440,000 square feet, are set to transform how we perceive, occupy, and operate the workplaces we commute to every day. To implement the vision of its prime home, Uber partnered with AlfaTech Consulting Engineers, Quezada Architecture, SHoP Architects, and RMW Interiors to deliver a project redefining the norms.

“Drawing on its urge to revolutionize the transportation industry, Uber is pushing the frontier with its innovative headquarters in San Francisco’s Mission Bay district. Through a rarely seen integration of building systems, future Uber employees will enjoy the perpetual benefits of a workplace adapting to its occupants.”

— AlfaTech

AlfaTech provided design/bid/build style Mechanical, Electrical, and Plumbing (MEP) engineering, lighting design, and Technology (low voltage, security, audio/visual) services throughout the project. Life-cycle cost analysis, energy benchmarking, and computational fluid dynamics were critical tools for the design effort. AlfaTech is part of the construction administration effort as the buildings arise and serve as the engineer-of-record for mechanical and electrical installations. A&S Inc. was retained as a minority-based firm in the capacity of the plumbing engineer-of-record for C+S scope of work. Quezada Architecture served as the architect-of-record for the project.

At a Glance

OWNER: Uber Technologies Inc.
LOCATION: San Francisco, CA
SIZE: 440,000 SF
COMPLIANCE: LEED Gold, WELL Silver, Title 24 2013 and 2016, PG&E Savings by Design
SERVICES: Mechanical, Electrical, and Plumbing (MEP) engineering, lighting design, and Technology (low voltage, security, audio/visual)
MEP LEAD: Jeff Fini
ARCHITECTS: Quezada Architecture, SHoP Architects, RMW Interiors
GENERAL CONTRACTORS: Truebeck Construction

Occupant-Centric Workplace

Under the auspices of Uber’s thought leadership, the design teams disembarked on a journey to create a new workplace. It started with the occupant, whose hub is the “neighborhood,” an island of the open office. Versatile hoteling stations, collaboration spaces, and conference rooms were natural components. An intelligent control system was masked within each neighborhood, gently nudging critical environmental parameters toward increased comfort. The near-invisible air-conditioning systems were designed to respond frequently, cooling the occupant at temperatures closer to that of the skin than the normative systems. Simultaneously, office and cafeteria lighting systems mimicked the circadian rhythm using an attentive balance of daylight, indirect, and artificial light. Taken together, the expression was a workplace in tune with its environment.

While the inspiration to the design teams was Uber’s mobility services, the premise was Uber’s culture of inclusion, diversity, and encouragement of connection between employees. Because the strategy was instilled from the top down, all floors of Uber’s Mission Bay Campus were intended to integrate, interconnect, and constantly acclimate. Thus, spatial constraints were released to promote flexibility.

Vertically Integrated Ascent

The building systems emanated from a combination of ideas, which led to a concept of centripetal aesthetics and engineering. This was primarily articulated with the buildings’ illuminating atria system that connected two of the towers and the seamless control and air-conditioning systems that adapted the interior environments to the occupants.

Uber Mission Bay Campus. Rendering courtesy of SHoP Architects.

In summary, the buildings’ eco-friendly features consisted of:

Two passively conditioned, interconnected atria
Shaded facade with automated natural ventilation
Chilled sails and occupant-controlled underfloor air-distribution systems
High-performance LED lighting with an occupancy-driven network-based lighting control
Graywater reuse and rainwater catchment systems
Integrated building automation, controls, and management platforms
Full air-side and water-side economizing
Fuel cells redundantly power building network operations
Urban garden
Solar domestic hot water system
PV-ready electrical system

Smart, Self-Sustaining Controls

An elaborate IT infrastructure provides the foundation for the building technology systems, boasting more than 600,000ft of copper and fiber cabling, 20 IT rooms supporting 167kW of network and server capacity. A robust Wi-Fi network distributed throughout the buildings provides secure and reliable wireless connectivity for end-user devices, building control systems, and public guest access to maintain fidelity to the design intent; these constituted pertinent integration points to the control system. Individual sub-system communication protocols are compiled to the requirements of the Integrated Building Management System (IBMS) architecture, enabling the one-platform control approach desired by the client.

Two 250 kW fuel cells were selected to power campus IT loads around the clock fully. Consequently, the campus harbored a self-sustaining cloud that could manage the building systems regardless of the status of the normal power grid. The demand-response capability could automatically turndown 15% of lighting power at the utility's request. The method relieved the power grid during certain pre-designated peak power days.

Architecture of the Integrated Building Management System.

Passive Before Active Atria

The two-building atria system, perforated with hanging balconies and slab openings, provided above-grade connections between Mission Bay 1 and 2 towers (1455 and 1515 Third Street, respectively). From the get-go, the atria were delimited as passive environments to encourage occupants’ connection to the exterior environment. This was aided by a radiant heating/cooling floor system coupled with a fan-assisted, automated natural ventilation system. In the event of wind conditions compromising the structural integrity of the operable windows, mechanical ventilation supplies fresh air. Adaptive thermal comfort modeling complies with our client’s expectations using refined, meshed geometry computations.

These innate characteristics of the atria equipped the campus with a near-effortless buoyancy vis-à-vis the outdoor conditions; it significantly reduced energy compared to any active building component. Meanwhile, transitory comfort could be upheld and regulated by the mixed-mode system on a floor-by-floor basis.

Mission Bay Tower 2 Atrium Facade and Operable Windows. Image courtesy of AlfaTech.

Ecological Engineering

Dual-temperature, high-efficiency water-cooled chillers with condensing boilers were treated as the assumed central plant condition; however, conceptual studies were also undertaken for geothermal heat pumps and a condenser water heat exchange with the San Francisco Bay. Due to the site's limitations and permitting concerns, neither of the alternatives was pursued.

Another focal point in the conceptual engineering design was the perception of wind comfort across the proposed campus. Steady-state computational fluid dynamics (CFD) analysis predicted the worst-case wind velocity vectors as a function of elevation above ground. The results informed locations of parapets and trees to shield sensitive pedestrian walkways and building openings from excessive wind forces.

Uber Mission Bay Wind Study (Early Design Phases)

The sleek, integrated design was predicted to offset energy use regardless of season. Efficient mechanical systems and low-energy lighting spurred the preponderance of energy use reductions. Water conservation stemmed from a discrete system of pipes and basins that collect graywater from lavatories and rainwater from the rooftops to repeat water use elsewhere. A diminished ecological footprint naturally aggregated from these conditions of the building systems.

Hyrodynamism

Alternate water practices were enabled by collecting greywater and rainwater into a central treatment system. Therefore, safe and fully recycled water was available for flushing at all toilet fixtures. The water reduction was predicted to reach 40% over the applicable environmental standard, with 2,100,000 gallons of domestic water conserved annually. UV disinfection and on-site generated hypochlorite for chemical treatment were two important features of the water reuse system. The water quality was controlled to the public health department’s accepted values.

An array of solar thermal collectors produced domestic hot water 10 times the demand of a modern shower. Comprised of 16 individual collectors, the 500 square feet of aperture area supplemented the domestic hot water system. The system achieved 650,000 BTU/hr of thermal power at rated conditions.

Schematic of alternate water system source-supply treatment process. Image courtesy of the San Francisco Public Utilities Commission.

Energy Economization

The astute combination of chilled sails and underfloor air distribution contributed to the lion’s share of the campus’ state-of-the-art HVAC. Effectively, the chilled sails conditioned workspaces to thermal uniformity while the underfloor air-distribution system supplied fresh air to occupants. The strategy relied on tempered chilled water and high-temperature underfloor air distribution. The latter was served by fan-wall air-handling units equipped with Variable Frequency Drives (VFD) and MERV13 filter frames capable of accommodating carbon filtration for WELL building compliance. The chilled sails were divided into perimeter and interior office conditions. Both were visually equivalent but used two disparate thermal conductors, carbon graphite and aluminum, yielding higher cooling capacity at the perimeters.

Three-dimensional view of the underfloor air distribution system, office workstations, and radiant panels.

The central systems consisted of dual-temperature, chilled water loops with magnetic bearing chillers, variable primary pumps coupled with injection pumps, and full water-side economizing using variable speed cooling towers. On the heating side, condensing water boilers maximized efficiency by exchanging latent heat between vaporized and condensed water originating from the flue gases normally escaping the building energy systems. The full-service kitchen included variable flow-hoods with safe shut-down, and fresh air delivered in tandem with a pollutant control system scrubbing particles from the grease exhaust.

Energy modeling showed that the savings over the industry baseline were targeted to conserve 25% of the energy use, corresponding to approximately 1,100,000 kWh per year. The passive atria were critical energy use reducers by way of its more tolerant interior climate. Effectively the atria act as a double-skin façade system, greatly reducing thermal loads at the south and west building facades. The glazing types ranged from low-shading, fritted glass at office spaces to high visual transmittance glass at transitory spaces.

Perpetual Synergy

The clout of Uber’s Mission Bay Campus was the plethora of systems to conserve and monitor the use of water and energy across the daily workspaces. Where measurements and verifications precisely defined the performance benchmark, continuous improvements depended on big data analytics which could identify additional operational synergies and therefore consecutive savings.

The building energy systems needed to swiftly and accurately adjust to changing interior and exterior environmental conditions. Key components included local sensing, integrated sequences, and an on-site weather station. The interactions between the occupants, the buildings, and the ambient, were at the heart of the architectural and engineering systems; with them, a new experience took shape which was targeted to permanently lower environmental metrics on the magnitudes of 1,100,000 kWh in reduced energy use and 2,100,000 gallons in reduced water use.

Case Study: Uber Mission Bay Headquarters