While programmable thermostats are touted as a sure-fire way to reduce your energy bill, they may not be the panacea to large power bills that manufacturers would have you believe. For a smart thermostat to really be effective, you must educate users on how to get the most out of their heating system. Let’s look at programmable thermostats to see if they really do save you money.
Heating and cooling account for the lion’s share, averaging a weighty 45% of your monthly power bill. Much of this heat goes to conditioning empty spaces when occupants are away at work or school or sound asleep in their beds. It makes sense that a thermostat that adapts to occupancy levels would save you money. Consider that you save about 1% on your energy bill for every 0.5°C you turn your thermostat down and it does seem like you could be saving wads of cash.
You see, smart thermostats are programmed to turn down the heat in your home to a pre-determined setting when you are away or asleep. Before you are scheduled to arrive home or wake up, the smart thermostat turns up the heat so your home is always cozy.
It does sound good, especially when manufacturers claim that homeowners can look forward to savings of 10-30% on heating and cooling costs. At this rate, you’ll make back your initial investment in two years and then sit back and enjoy the savings.
However, studies show that this isn’t quite what happens in actual households. The 30% energy-saving Holy Grail seems to only be achievable under lab conditions or with users who are extremely disciplined. Some studies put the figures closer to between 6.2 and 6.8% while one study in the USA found that having a programmable thermostat actually resulted in an energy bill that was 12% higher.
Educating occupants means ensuring that the thermostat is actually lowered when no one is home and avoiding large fluctuations in temperature as it takes too much energy to reheat homes that are too cold. Many home and condo owners think that turning the heat right down will save them more.
The ideal range for a smart thermostat is around 20°C when you are home and 6-8°C lower when you are away or asleep.
From the US EPA: “Consumers are often advised that installing a programmable thermostat can save them anywhere from 10 to 30% on the space heating and cooling portion of their energy bills. While reliant on proper use of the programmable thermostat, such savings are easily true in theory; however, there needs to be more field-tested data to better substantiate savings claims. Analyses from recent field studies have suggested that programmable thermostats may be achieving considerably lower savings than their estimated potential.”
If you are looking at finding ways to save energy, a programmable thermostat is a step in the right direction, but it must be a part of a comprehensive energy-saving strategy that looks at all aspects of your home and consumption.