A reference design for parking garages

SFO Long-Term Parking #2

Beyond Zero-Net Energy

SFO LTPG2 is the new 2.1Msqft parking facility at San Francisco Airport. SFO intends to be the first Zero-Net Energy (ZNE) airport in the world, and to contribute towards that goal this facility must generate considerably more energy than it consumes, or ZNE+.

We expect the garage to generate an impressive 278% energy surplus, and lighting is a big part of that story. The project won an Illumination Award of Excellence in the Energy and Environmental Design category

Lighting for personal security

Lighting design can be a technical discipline. There are published lighting metrics we generally design to, but there are also aspects of lighting quality that aren’t well captured by the metrics.

For example, large amounts of light emitted at shallow angles increases uniformity on the floor which looks good in a calculation, but can be a source of glare in person.

Centering the User

Of course, even on a ZNE+ project there’s a lot more to good lighting design than just delivering the lowest possible energy consumption. Lighting design is always an integrative process which attempts to reconcile a multitude of different and often contradictory requirements. It’s important to stay focused on the end user experience though the entire design process.

Lighting controls design is crucial for Zero-Net Energy...

While the adoption of LED technology has reduced energy efficiency, the greatest energy savings are to be found by turning off the lights when they’re not needed. Therefore, lighting controls design is crucial to attaining ZNE+ performance.

...but garage lighting controls are usually pretty bad!

In a typical garage each fixture is controlled by an onboard sensor which triggers just that fixture. Users tend to feel that the sensors respond too slowly, and that the visible brightness changes are distracting. To compensate, owners set the ‘unoccupied’ lighting level to be quite high, or disable the sensors altogether. Garages are 24/7 facilities, so bad lighting controls can waste a lot of energy. To compensate for the limitations in occupancy sensor range, at LTPG2 the fixtures are networked into zones so that entering a zone triggers adjacent fixtures as well. The result is a better, more seamless experience for the user.

Visitors pass through “Coding,” an immersive art installation designed by Johanna Grawunder integrated into the elevator tower. Magic mirror panels dot-dash messages in Morse code; yellow steel tags on the exterior mullions recall the cardinal directions; luminous ceilings and volumes color-change and become kinetic elements that amplify the up/down movement of travelers. The elements are dynamic day and night through the use of materials that respond to reflection, luminosity and color-changing light.

An immersive art installation

Project Team

For many visitors, the garage is the first and last impression of their travel journey. We think all of this adds up to a different, maybe slightly more thoughtful parking experience.

Owner: San Francisco International Airport (SFO)
General Contractor: Nibbi Brothers
Architecture: Kwan Henmi/DLR Group and FMG Architects
Electrical Engineer: BAC Engineers
Electrical Contractor: Redwood Electric
Light Artist: Johanna Grawunder