Stefan Storey, PhD. is co-founder and CEO of Sensible Building Science (SBS), a sustainable technology start-up that aims to make buildings smarter and more responsive to the needs of occupants. Stefan has an interdisciplinary engineering background and is a specialist in building science. In this interview with Ken Sinclair, Publisher of (and regular columnist for The Connected Contractor eNewsletter), he discusses the future of building automation.

SinclairWho is Sensible Building Science? What is your vision?

Storey:  We are a Vancouver-based team of sustainability and computer science geeks. We have the vision to revolutionize how buildings learn from people. We are now over two years old, and already have over a million square feet of commercial space using our energy saving solutions with analytics serving over 100,000 occupants in real-time. We are dedicated to helping building owners and managers attain comfortable and energy efficient buildings with our automated virtual occupancy metering solutions.

SinclairWhat is virtual occupancy metering?

Storey:  Virtual occupancy metering (VOM) is a method of people-counting without the need for physical sensors. It’s like Google Traffic, but for indoor environments. Our solution, called Bridge, uses existing Wi-Fi activity data to generate VOM data and enable occupant-demand control of building heating, ventilation, and air conditioning (HVAC) systems, without the need to install new equipment such as motion detectors, video cameras, or physical sensors.

SinclairHow can Bridge result in  energy efficiency and improve comfort?

Storey:  The Bridge finds energy savings from optimized automation of  HVAC control, by communicating occupancy changes to the Building Automation System (BAS). The Bridge is a good solution for busy commercial buildings. With over 90% accuracy and a response time of 180 seconds, it’s much faster and more precise than CO2 response. The Bridge is also low maintenance because it uses existing Wi-Fi infrastructure which means there is no sensor calibration or maintenance; it can also help facility owners by reducing the number of comfort complaints. Additionally, because our solution can detect unscheduled occupancy, we can trigger real-time HVAC response wherever people gather making sure people have optimal comfort.

SinclairDo you have any measurement and verification data. Have you proven it works?

Storey:  We have completed extensive testing at three different university campuses. Our M&V methodology, which was reviewed and approved  by our British Columbia’s utility provider (BC Hydro), has measured an average of whole-building energy savings of 5% annually. Most of these saving have been gained in building zones that have variable occupancy. It’s surprising how often rooms have low occupancy; these areas are perfect for deep energy savings. In lecture halls with periodic classes, we have reduced fan-time run hours by 20-40%. Conversely, where people are gathering at off-schedule hours, the HVAC will be woken-up activated which will consume more energy than normal. Of course, comfort is more important than energy savings, so at these times HVAC is using more energy than the baseline . However, on average, almost all building areas gain savings. The payback on the solution has been proven between 2.7-5.4 years, faster than most demand-side solutions.

SinclairWhat kind of systems can you integrate to? I hear you have been creating partnerships. Who are you working with?

Storey:  When we install the Bridge, the software interacts with two systems. On the Wi-Fi side, we have been working extensively with Cisco Systems data. We have found the Cisco data to be very reliable and stable. Cisco really care about the quality of their data and they have been very supportive of our innovation, it's been great working with them. On the BAS side, we can integrate to BACnet, KNX, LonWorks and more. We’ve been working with our partners at UBC who have been integrating to BACnet on Johnson Controls, Siemens, and Delta. However, we need a reasonably up to date DDC system for integration. Very old legacy systems are a significant challenge. In terms of reprogramming and rescheduling building controls, we’ve been working with SES Consulting who have extensive experience with modelling and scheduling ventilation protocol for BAS systems. Working with SES has ensured that our clients have optimal strategies to maximize savings and ensure comfort.

SinclairYou’ve mentioned comfort several times, why is this of particular interest to you?

Storey:  For occupant comfort, a sense of agency and connectivity is very important. Research from UC Berkeley has shown that when occupants have access to environmental control, such as access to an operable window, they have an improved sense of comfort and wellbeing. Innovative companies like Building Robotics, with their groundbreaking Comfy solution, have taken tremendous strides forward in connecting occupants to building comfort. Comfort really matters, particularly for workforce performance, health and wellbeing. Our Bridge solution works 24 hours a day helping buildings be aware of their occupants. We’re happy to be a part of the comfort solution.

SinclairWhat is next for Sensible Building Science?

Storey:  We want to help buildings learn from how people move and interact with their physical environments. We have a major new machine learning project underway for Bridge which will open up a new ability to conduct predictive control. The old method of building controls is limited by being mathematically conditional and rule-based. We will be taking an entirely new approach that will enable facility owners to take full advantage of our new anticipatory smart controls. We have formed a partnership with UBC Computer Science to accelerate our R&D and get innovation to facility managers and owners for continuous Agile testing.

SinclairAny words of advice to upcoming start-ups that want to get into the growing world of sustainability innovation?

Storey:  Partnerships and mentors are so important in the early days; listen carefully to your mentors and work hard for your partners. We could not have moved forward without the advice and support of our friends and colleagues at UBC, Cisco, Wavefront, e@ubc, Prism Engineering, SES Consulting, Chipkin Automation, NRC-IRAP, Vancity, BCIC, and the Vancouver Economic Commission. We are immensely grateful and owe a ton of thanks to all of these groups.