When I became a university student, I stopped routinely taking the elevator. I originally did this out of fear of gaining the infamous “freshman fifteen.” I thought that by introducing more stairs into my lifestyle, I wouldn’t wind up as one of those university students who claim they never have time for physical activity.
As I started my elevator boycott, many people asked me if I chose the stairs over the elevator for environmental reasons. I usually said that’s just a bonus - but is it actually? If people stopped taking elevators, would it benefit the environment?
If you take a quick google search into this issue, there are a lot of variables at play. First off, there are many different types of elevators and many ways that they consume energy. The oldest elevators in use today have lower efficiency AC/DC motors. Over the years, modifications and improvements have been made to these motors improving their efficiencies, with the latest elevators today using energy regeneration technology that harnesses energy from an elevator’s braking.
The electrical consumption inside the elevator for lighting, fan and temperature control are factors to consider as well. Then, there is the consideration of the height of the building, the number of passengers and the frequency of the elevator’s usage.
Despite all these possibilities with the numbers behind elevators, rough calculations and estimations are available from reliable sources. An example of one of these statistics is from the Institute for the Protection and Security of the Citizen of the European Commission, which states “one travel by elevator of 15 seconds can be equivalent to have one incandescent bulb of 60 W switched on for one hour.”
In terms of how much energy that is on an annual basis, the American Council for an Energy-Efficient Economy calculated that an average contemporary elevator in a low rise building makes 100,000 trips a year using 1,900 kW hours. This is roughly equivalent to an annual production of 930 kg of CO2. Using these calculations, that means that by opting to take the elevator over the stairs, you would save an average of roughly 0.30 kg of CO2 a trip. So if that number is so small, why do people have this belief that elevators are energy inefficient?
It is because the elevators themselves can actually be highly inefficient whether there are passengers in them or not. Major elevator companies like OTIS, Kone and ThyssenKrupp have all started to dedicate research in recent years towards energy efficient technologies and environmental considerations. For example, the Gen2 elevator and ReGen technologies from OTIS provide energy savings of over 50% and 75% respectively in comparison to a conventional elevator system. Gen2 elevators use a more energy efficient building process and set of materials that do not require the need for any polluting lubrication. OTIS’ ReGen technology collects energy normally lost from an elevator braking and uses it to increase the system’s efficiency.
So in the end, it appears that people should be advocating for the introduction of energy efficient elevators rather than the boycotting of elevators all together. While people can still chose to avoid taking the elevator for health reasons or to save that extra 0.30 kg of CO2, we should also appreciate that elevators do have extremely important roles in buildings (ex: increasing accessibility and transporting of materials).