Fiat Lux: Personalized Automated Lighting Controls

1. Fiat Lux: Personalized Automated Lighting Controls Omar Rehmane, Andrew Krioukov, David Culler

2. Commercial Buildings 37% of electricity in US $107B annual energy bills Lighting is 25% of building power

3. Lighting Control in Buildings • Residential: personal control allows for energy efficient use • Commercial: shared space, automated system inconvenient and inefficient use • Schedules • Override buttons • Motion detection

4. Sutardja Dai Hall Software controllable! 3 years old 7 floors, 140k sq. feet Collaboratories, offices, classrooms, auditorium & nanofab

5. 7th Floor Lighting Power Meter Controller & Relays

6. Old Controls • 10:00 AM – 6:00 PM: Lights run on a schedule • Other times: 2 hour timer • Interface: Physical wall-mounted button • Hard to control brightness

7. Zone Selection

8. Timer Extension

9. Persistent Savings (4th Floor)

10. Breakdown of Savings

11. Issues • Requires user action to indicate presence • How long to make the timer? • Wasted energy vs. user input demand trade off

12. Proposed Solution • Cross-platform system tray app, Fiat Lux • Automatically keeps the lights on for users

13. Developing Apps for Buildings sMAP/ REST API HTML/HTTP MySQL Python Control Process Python Django sMAP Gateway BACnet Fiat Lux

14. Challenges (and their solutions)

15. There are also laptop users in SDH They might continue to keep the lights on from home inadvertently Only allow users in SDH to keep the lights on MAC address fingerprinting Improving localization Check IP address if wifi is not active This also means that lights will automatically start if Fiat Lux is running when the user comes in Location

16. Sutardja Dai Hall has desktop users that lock their screen rather than logging out Due to automated extending, this can keep the lights on if the user forgets to stop Fiat Lux Stop extending the lights for idle users Determine idle status through the system idle time (taken from OS) Decided on 5 minutes as an appropriate idle time Idle Users

17. Timer extends to either 3 hours or 1 hour This means the lights can be on in an empty zone/floor for up to 3 hours! Fiat Lux extends the timer automatically, so the frequency doesn’t matter Extend the timer to 2 minutes every 1 minute (allowing for any communication delay) Maximum wasted “on” time: 2 minutes Wasted Time

18. Users with conflicting brightness settings will constantly have the lights switching brightness settings More disruptive than lights simply turning off once in a while The web client solves this by maintaining a single brightness control per zone Fiat Lux emulates this “most recent wins” model by extending the current setting during automatic updates The user must manually change the setting to update brightness in the room “Brightness Wars”

19. Overall Control Logic

20. Advantages • Automatic extension removes input demand • Only extends the lights for active users in the building • Maximum wasted time is 2 minutes • Eliminates energy savings vs. user input demand tradeoff

21. Next Steps • Phone version of Fiat Lux • HVAC controls

22. Questions?