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bluGill an hour ago

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.

quickthrowman 10 minutes ago | parent [-]

> I wouldn't be surprised if most of the savings was the new lights are LED while the old only incandescent was available

It’s definitely not the lighting, you only need a few thousand lumens to have bright elevator lighting. If you need 4000 lumens, that is (5) 60W incandescent lamps, switching to LEDs that do 100 lumens per watt (8W lamp) saves you 260 watts/hr.

The new elevator uses a VFD (they call it a VVVF) to control the motor which is where virtually all of the gains come from. Lowering the speed of the motor lowers the power usage, it’s a non-linear relationship but a motor spinning at 75% speed uses 1/4 to 1/3rd of the power that it would use at full speed. The motor is probably somewhere between 40-150 HP or 30kW to 113kW (after inrush at 100% speed)

> They likely only have whole building power consumption

You can easily measure the power of a single circuit or single panelboard using a submeter: https://www.shopemondirect.com/catalog/shop/Shop-E-Mon-Direc...