In the past few years, the residential controls market has seen an influx of smart thermostats from brands like Nest, Ecobee, Honeywell and others. These devices are a great addition to any home and will save occupants money in the long-term. When it comes to hotels and other commercial properties, however, these products can fall short. Here are six reasons why residential smart thermostats aren’t right for the hotel environment.
The first thing to know about residential smart thermostats is that wireless communication is accomplished using the occupant’s Wi-Fi connection. This isn’t surprising, since it’s a requirement for Energy Star certification and not particularly onerous on the occupant’s internet bandwidth. In a commercial building environment, however, there can be many devices throughout hundreds of rooms connected to the internet at the same time. Adding thermostats to the list of devices consuming valuable Wi-Fi resources isn’t wise.
Many commercial smart thermostats avoid Wi-Fi and opt to use the Zigbee protocol. While this solves some of the issues associated to Wi-Fi, such as higher power consumption, it doesn’t guarantee there won’t be interference because both protocols operate at the same 2.4GHz frequency. The best option is to avoid the Wi-Fi network completely by using a proprietary communication protocol at around 900 MHz. The longer radio waves penetrate building materials easily without the need for network repeaters or signal boosters, and of course, avoid any interference with guest Wi-Fi.
2. Power Consumption
There is a reason why all residential smart thermostats are wired—they all draw a considerable amount of power because of their Wi-Fi connectivity. This works fine in most residential scenarios where existing controls are already wired to the heating, ventilation and air conditioning system. But throughout many commercial properties in North America, especially in the midlevel category, the typical HVAC system is made up of packaged terminal air conditioners that are not controlled by an existing wall thermostat, but by the dials or controls on the unit itself. In those cases, retrofitting the room to run wires can be costly, and therefore a wireless solution is preferable. Most commercial energy-management systems have wireless solutions available that function on batteries.
3. Self Learning vs. Location Based vs. Occupancy Based
Depending on the residential thermostat, there are a few different ways they achieve energy savings. Here are ways residential smart thermostats operate:
- Nest is a self-learning thermostat that saves energy by learning your typical schedule. By changing the temperature setpoint in the morning when you wake up and down again when you leave for work or go to sleep, Nest eventually does it automatically for you. This approach to energy management in homes is ingenious because occupant patterns are reasonably static and predictable.
- The Honeywell Lyric thermostat is a hybrid that can use programmable scheduling from the user and location data from the user’s smartphone. When residents approach a radius around the house, the thermostat will prompt the HVAC system to heat or cool the home to the occupants' preferred temperature by the time they get there.
- Ecobee thermostats work similarly to the devices mentioned above but provide additional remote sensors for bedrooms to make sure temperature setbacks don’t occur when occupants are at home.
All these methods of achieving energy savings can work well in a home setting but have one thing in common that is their proverbial kryptonite—random occupancy patterns. Residential thermostats rely on some type of schedule, whether it be learned or programmed. But hotels and other types of commercial buildings don’t have predictable, fixed or learnable schedules due to the transient nature of the occupants.
Smart energy-management systems for hotels are equipped with built-in passive infrared motion sensors that continuously scan their surroundings for motion and body heat. Armed with this information, hoteliers can accurately ensure that temperature setback only occurs when the room is empty, thus insuring an optimal experience for the guest.
4. Remote Management
Whether you’re a real estate investment trust with hundreds of properties under your purview or an owner of a handful of properties, most customers want to be able manage and monitor temperature and other parameters from a distance. With a Nest thermostat, operators can only manage up to three properties, but an energy-management system provides the hotel enterprises with the ability to manage an unlimited number of properties.
An EMS brings more actionable data to the table, too. Beyond controlling the temperature in the room, an EMS can tell you how many kilowatt hours have been saved on a daily basis, how many hours your rooms are occupied in a given month and which rooms are having trouble reaching the occupant’s setpoint, which is a great segue to the next point.
5. HVAC Diagnostic Alerts
If the HVAC system at your commercial property is malfunctioning, inefficient or on the verge of breaking down, you’d want to know, right? If you’ve ever had your furnace stop working in the dead of winter, you’d understand. Some residential smart thermostats do provide limited alerts.
For example, a Nest thermostat will alert users to power cycle interruptions, but only with forced air heating systems. That might be fine in a residential setting, but inadequate in a hotel or other commercial building that only cools or has a non-compatible HVAC unit. Fortunately, most commercial energy-management systems can notify managers when HVAC systems are experiencing issues.
Here’s how HVAC diagnostic alerts work: EMS thermostats collect and aggregate a lot of data. One key data point to measure is the number of minutes the HVAC unit spends heating or cooling a room. This is done for each room at a property. By collecting and aggregating this data, the EMS establishes a baseline for typical usage in an average room. When the system encounters an HVAC unit that is well outside the average, a customized alert is sent to the maintenance person at the property so he/she can promptly identify and rectify the problem before a complaint is received or equipment is damaged. As they say, “an ounce of prevention is worth a pound of cure.”
Great news: A commercial energy-management solution is not prohibitively expensive. Research shows that a typical residential smart thermostat will run somewhere between $150 and $250 each. Although these systems are relatively simple to install, some people still may hire a professional HVAC contractor to avoid dealing with wiring, increasing the overall cost. EMS thermostats are priced in a similar range and also can be self-installed by most facility engineers or maintenance people with the help of technical support resources. Don’t forget about those rebates available from your local utility companies. Both commercial and residential smart thermostats are eligible for rebates from most utility companies by up to as much as 50 percent of the system cost.
In conclusion, hotels, senior living communities, student dorms and other commercial properties have unique occupancy patterns that make them ill-suited for a residential smart thermostat. When considering the type of smart thermostat system to install at your property, it’s always wise to consider the unique set of circumstances and evaluate multiple technology providers to establish the best fit for your property.
John Attala is the marketing director for Verdant Environmental Technologies, a provider of energy-management solutions for the hospitality industry.