A High Performance Building Control Concept for Engaging

Occupants as Users of Efficiency Controls

Shanti Pless, Jen Scheib, Paul Torcellini: NREL

Tom Hootman: MKK Engineers

October 2014

Occupant Engaged: A High Performance Building Control Concept for Engaging

Occupants as Users of Efficiency Controls Shanti Pless, Jen Scheib, Paul Torcellini, NREL

• As was recently highlighted in recent Pathways to ZNE Buildings in California,

understanding occupant interactions with high performance building controls can lead to further energy savings opportunities. In general, the building controls industry has trended toward more automation for energy savings, resulting in complex systems that have removed occupants from engaging in better controls. In this paper, we propose a solution for a simpler controls philosophy that engages occupants, which can help lead to lower energy use and more satisfied users. This control concept, which we have coined Occupant Engaged, is based on the idea that control systems can be designed and operated to require occupant engagement to take a system from the off to occupied state. And then the system’s automation will turn off or go to unoccupied state if the occupant “forgets” to turn off the system. This paper documents specific lighting control, plug load controls, glare controls, and HVAC control implementation successes of the Occupant Engaged controls. In one case, savings from Occupant Engaged lighting controls in a partially daylit break room saved 70% in lighting energy use as compared to a typical occupancy sensor fully automatic lighting control system. In general, we have found occupants will engage with their systems, and energy savings from these simpler controls are greater than fully automatic controls.

CONTROL

Automation vs. Manual Control

• “In part due to the unpredictability of user behavior, the building industry overall has embraced automation as a means of reducing energy waste

• However, development and evaluation of automation has not adequately accounted for building users’ desire for control or the potential energy savings from manual versus automated control

• Better integrating the human dimension in designing and selecting automation can help lead to lower energy use as well as more satisfied users”

Road to ZNE: Mapping Pathways to ZNE Buildings in California. Heschong Mahone Group, Inc.

People in Buildings… • “will adapt the building, systems, controls and features

to their needs and wants. This is not to say that they will adversely affect the carefully crafted building and system designs, but they will make things work for them if they can.

• can and do adapt to new designs and learn how to use buildings”

“Therefore, strategies for supporting occupants on how to maximize their building’s energy efficiency attributes

should be developed”

Road to ZNE: Mapping Pathways to ZNE Buildings in California. Heschong Mahone Group, Inc.

A Solution: Occupant Engaged

• A control philosophy for engaging occupants in high performance buildings operations as active users

• Requires occupant engagement to take a system from off to occupied state – Default mode is maximum efficiency mode

• off or setback

– No automatic ON – Occupant engages control to turn on if service needed

• Intelligence to turn off or go to unoccupied state if occupant “forgets” to turn off

– MUST have simple local occupant engagement interface • On/off switches the best

Occupant Engaged: Current Applications at NREL

• Vacancy Sensors for Lighting – Manual ON, manual OFF, with automatic dim and OFF

when vacancy sensed

• Timer-OFF controls for plug loads with manual ON

• Local glare control – Local manual tint of electrochromics, manual clear with

automatic timed clear

• Operable Windows for Natural Ventilation

• Local USB powered desktop fan – Turns off when computer goes to sleep

Occupant Engaged: Applications in Development or Proposed

• Shades with Occupant Engaged controls

• HVAC Occupant Enabled

– Local ventilation

– Local heating/cooling

• Real time Personal Energy Efficiency Feedback System

• Vacancy sensor LED task lights

• USB desktop hub with vacancy sensor

Occupant Engaged Development at NREL

• Started with large scale vacancy sensors application in all daylit spaces in RSF – Most successful in enclosed offices, conference

rooms, and intermittently occupied daylit zones such as corridors and break rooms

– Vacancy sensors in daylit break rooms resulted in 70% energy savings over a occupancy sensor • Measured savings by logging occupancy and lighting

energy use

– Similar to current 90.1 and Title 24 Vacancy Sensor lighting control requirements

Occupant Engaged Development at NREL

• Next application is plug loads – Has become the standard for office space in 2013

• Electrochromics in ESIF – Local zone control for south windows

In general, we find that occupants will engage when they are given the chance and really need the service…

– But are indifferent and don’t really need it as much as we thought • Occupants turn on open office lights when daylighting is providing

less than 10 fc

Expanded comfort savings are realized in temperature, local air movement, light levels, and glare control when occupants have local control over these conditions

– Lighting control in conference rooms

• First press of ON button in partially daylit conference rooms with native dimming capability should bring lights on to a dimmed state (35%)

• User has to hold dim UP button to get full lighting output if they really want it…

• Vacancy automatically shuts off after space becomes unoccupied

– We see this as a promising application for open office Personal Lighting Systems as well

Additional examples in Use- Lighting

• Occupant Engaged Task Light

– integral vacancy sensor to turn off if not turned off manually • Not an occupancy sensor task light!

– USB powered to match DC power supply with DC load

Does not yet exist…can we invent this?

Future development needs- Lighting

• Manual on button for power strip with manual off and timer off after 11 hours

• Controls task light and other office space loads afterhours

• Tie as many loads to USB ports that turn off when computer goes into automatic sleep mode

• Task lights (does a desktop USB powered task light exist?)

• USB fans

• Chargers

• Monitors

• USB hub with vacancy sensor • Invent this too…

Examples in Use- Plug Loads

GLARE CONTROL

– Glare control with Electrochromics

• Manual window tint switch for local zones, with automatic timer clear after 2 hours

– Glare control with shades – in development

• Manual roller shades down, with manual up and with an automatic up timer for 4 hours (or very slow automatic raise over 4 hours) – Need to develop this…

Examples in Use

HVAC Applications • USB powered desk top fans

– Controlled with USB power in laptops

• Building goes into “Passive” mode – Requires occupants to open windows/turn on local fans/air to

meet local comfort

• Other possible control systems – Lab air with manual occupied switch – Turn off HVAC when OA conditions are ok for natural ventilation – Local/Personal HVAC control system for personal heat pump

• Similar to car climate control for an office space – invent this too

Occupant Education? MUST have simple occupant engagement controls! • You have light switches- you can use them • If you open a window – close it • If you are stuffy- open your window • If you have a local glare issue, pull your shade • Turn on your power strip in the morning • Opt-out of efficiency default mode into occupied/energy use mode

• Occupants have to and will “figure it out” • “Hassle Factor” of controls for efficiency gains

– We would watch the same channel on TV all the time if we didn’t have a remote control…

– Actual office lighting levels measured before occupants engage to turn on open office ambient lights are 10 FC and below

Feedback of Occupant Engaged Controls

• Blink warn when timer is up

• Occ sensor will turn lights back on for 10 seconds after vacancy is detected

– Operates as an Occ sensor to account for false off

– After 10 sec, manual on is required

• Returns to Vacancy sensor

Occupants need better feedback

– Building owners and operators lack a fundamental active element when managing the efficient, sustained operation of their buildings: the Occupant

– NREL has installed outlet-level plug load metering equipment at the workstations of 200 employees

– Data from these plug load meters can be used to:

• Inform ESIF occupants of their personal energy efficiency performance

• Incentivize energy saving behavior (leveraging the NREL Building Agent app)

State-of-the-art options for plug load metering and control:

Occupants Engaged with Real-time Personal Efficiency Score

Missing Link: Provide Feedback

to Occupants

Technologies Deployed in the ESIF

• Feed data from plug load meters into the Building Agent App

• Provide occupants with data to inform competitions and incentivize good behavior

• Incentives could include: • An “Energy Saver of the

Month” parking space • “Group Energy Saver of

the Month” ice cream social

• Gift cards

Technical Description of Proposed Work: Mock Up of Occupant Feedback

Occupants could be shown how they compare to their anonymous neighbors

Technical Description of Proposed Work: Mock Up of Occupant Feedback Continued

Occupants could be shown their real-time (and historical) energy consumption with simple visualizations. Performance will be linked to energy saving tips.

The Building Agent app enables occupants to quantify and communicate their comfort levels to the building.

Future Work with OE

• Continue development of OE Task light

• Continue development of OE Window shade

• Continue development of OE Personal heating/cooling solutions

• Continue development of OE USB power hub

• Identify development partners to bring OE products to market for future ZEB projects!

References:

• California Net Zero Roadmap – http://www.energydataweb.com/cpucFiles/pdaDocs/899/Road

%20to%20ZNE%20FINAL%20Report_withAppendices.pdf

• Henze, G. P.; Pless, S.; Petersen, A.; Long, N.; Scambos, A. T. (2014). Control Limits for Building Energy End Use Based on Engineering Judgment, Frequency Analysis, and Quantile Regression. 92 pp.; NREL Report No. TP-5500-60020. http://www.nrel.gov/docs/fy14osti/60020.pdf

• http://www.nrel.gov/continuum/energy_integration/living_laboratory.cfm

• http://www.sciencedirect.com/science/article/pii/S0360132314003564