I find things like this interesting, I guess everyone finds this normal but,

"Power consumption is down 45% - 50% annually."

Well is it 45 or 50? Is this a measurement or prediction or a random number? From an engineer or marketing? If prediction, why not saying so? Is this a range for several years depending on elevator usage?

Things like this irk me a lot.

Perhaps it ranges (if a measurement).

But my best guess is they simply _cannot know_ because the usage patterns of the new elevators will be different from the old elevators based on dispatching and sequencing and call systems. In other words, even if they know the exact consumption of the old system, and even if they expect precisely the same number of passengers per day, the _actual operating cost_ will depend on who arrives in the lobby, at what time, destined for which floors, and all other traffic patterns throughout the year.

I think the error bars are too high to say more than that. I doubt they did a measure of the power the original consumed, just an analysis of the system. They likely only have whole building power consumption, where HVAC is the majority of the costs: 1 degree difference in the weather or a couple tenants taking a vacation will make a much larger difference than the elevator.

I wouldn't be surprised if most of the savings was the new lights are LED while the old only incandescent was available - this is just speculation though, I have no idea. Every gear and every stretch of the ropes cost a little bit of efficiency and the modern system has less of those.