How To Evaluate Occupancy Sensors
Key Takeaways:
Occupancy sensors are highly differentiated by cost and functionality, choosing the right one is not easy.
Knowing what functionality is most important for your asset is key to purchasing decisions.
Occupancy sensors take much of the guesswork out of building management and operation. What started as a way for security to track intruders is now being used widely in commercial office buildings to enhance safety and efficiency. Occupancy sensors are key in unlocking all types of savings for buildings. When tied into other building systems, lighting, heating, and plug load energy management can be automated around what space is actually occupied.
Better yet, occupancy sensors can help reduce overall real estate costs by helping office managers understand what space is being used. To understand all the different types, check out our list. Below we’ll cover how to evaluate the right solution for you based on four key factors.
Before you get started, ask yourself how you want to use occupancy sensors. Do you want to simply know how many people are in the building or do you want deeper data, like who is using space and how they’re using it? Good occupancy trackers can integrate with third-party devices to share insights and leverage automated changes. How is the occupancy data being reported and displayed? Data is only as good as it is actionable. Knowing what you want from your occupancy sensors is the first step to choosing the right one.
Cost
Upfront costs are always the biggest pain point. While occupancy sensors can pay for themselves, most are not a cheap solution. Because of the varying types of technology used by different products on the occupancy sensor market, prices vary greatly. When considering the cost of occupancy sensors, think about installation and maintenance fees.
Next, consider how many you will need. On the low end of pricing, simple break-beam sensors can cost as little as $2 but you’ll need quite a few. WiFi sensors are sophisticated tech that is pricey but most buildings only need one. Cameras are expensive, requiring costly installation and maintenance. Thermal sensors placed strategically above doorways and other high-traffic areas are an attractive option when the cost is the most important consideration.
Accuracy
Occupancy sensors are rarely 100% accurate because people are complicated and unpredictable. If accuracy is the most important part of your decision-making, it’s hard to beat cameras. Cameras tend to be expensive, but the data they provide for security, safety, and efficiency is hard to beat. WiFi and Bluetooth counters can be finicky, relying on certain settings on a user’s device, making them the most inaccurate type of occupancy sensors. All occupancy sensors get better with time as devices hone their ability within a space, comparing historical data sets to real-time counts.
Functionality
It’s not just about simply counting people. With more complex sensors, contextualized data can be layered in to paint a clearer picture of how space is being used and who’s using it. Thermal sensors and heartbeat sensors tell you almost nothing about occupants. WiFi-based occupancy sensors are the best for understanding occupants, scrapping available information from devices. With more data, WiFi people counting devices can provide valuable insights. One downside of functionality for WiFi devices is that certain user settings on phones can be turned off, preventing the device from counting that person.
Privacy
When collecting any type of data, serious consideration must be given to privacy. Occupancy sensors are a powerful data collection tool, opening up users to a whole range of privacy issues. If keeping data anonymous is the most important factor, simple technology will work better. Thermal sensors, break-beam sensors, and heartbeat sensors all track occupants anonymously without storing any information. Bluetooth beacons are also good at protecting privacy, as the system works on 1-way communication so no data is relayed back. Privacy laws around video cameras can be tricky to navigate.
