Heating costs for businesses are impacted by a variety of factors like climate and weather, age and efficiency of equipment, energy prices, and building size, but one factor impacts cost the most: thermostat setpoints. When businesses leave thermostats at the same temperature day and night, they waste money and energy by heating spaces outside of working hours. Thermostat setbacks during unoccupied hours are a simple and effective way to lower heating costs and save energy without compromising comfort for employees and customers.
A common assumption is that setbacks aren’t effective because the furnace must work harder to make up for the lost heat. While setting temperatures lower for a few hours or less may not result in meaningful savings, businesses occupied for 10 to 12 hours a day, five days a week can see significant energy savings when they set thermostats back 5 to 10 degrees during unoccupied hours.
The longer and lower the temperature is set back, the more impact it will have on energy costs. A determining factor in savings is the rate of heat transfer, which is how quickly heat leaves a space that's intended to stay warm. As the temperature outside gets colder and further away from the temperature inside, the rate of heat transfer increases. The closer the temperature is inside to the temperature outside, the slower heat will escape a building, so the furnace does not need to run as frequently.
Even setting thermostats five degrees closer to the outside temperature during unoccupied hours will result in a significant decrease in a furnace's runtime. For example, if a business is unoccupied every weekday from 6:00 pm to 6:00 am and all weekend, setting thermostats 10 degrees lower during unoccupied times could result in 20% to 40% energy savings.*
Setbacks can be easily automated by setting schedules on programmable thermostats. Wi-Fi enabled smart thermostats make maintaining setbacks even easier. Smart thermostats can be controlled from a computer or mobile device, allowing business owners or maintenance staff to change setbacks remotely. Businesses interested in replacing their old thermostats should check with their local utilities for smart thermostat rebate or discount programs like CEE’s free smart thermostat program for Xcel Energy commercial customers in Minnesota.
From no- or low-cost improvements like free smart thermostats to rooftop unit (RTU) replacements, CEE’s One-Stop Efficiency Shop team will help you find rebates and energy-saving HVAC solutions tailored to your building and budget.
*Energy savings from setbacks will vary depending on several factors including temperature reduction and length, equipment size, building envelope, and outside vs. inside temperatures.