Moving billions every day

Shifting the load: Energy-efficient elevators and escalators

By Morand Fachot

Elevators, escalators and moving walkways carry billions of people each day. This form of transport is used by a number equivalent to the population of the entire world at least every other day. These complex systems rely entirely on electrical or electronic parts to function. They account for 2 % to 10 % of the energy used in commercial buildings, so cutting their power consumption is important.

Nearly 160, but leaner and meaner

The safety elevator, as we know it today, was introduced nearly 160 years ago, and the first electric elevator 30 years later. The first patents for escalators were filed in the 1890s.

Escalators are the most convenient way of moving large flows of people continuously in large stores, railway and underground stations and airport halls. Elevators are more efficient at carrying smaller numbers of people on an intermittent basis.

Energy-saving systems

The current generations of elevators and escalators are significantly more energy-efficient than their predecessors. Innovative motors and machine room-less systems in which the motor, controller and other components are placed on top of the cabin, and regenerative braking systems that use the energy recovered when braking or slowing the cabin, help cut elevators’ power consumption.

Escalators can be made more efficient by:

  • Mounting sensors that will turn them off when not in use
  • Fitting energy-saving soft start systems that cut consumption when the number of people carried is low
  • Installing variable frequency drives and sensors to reduce their speed

IEC central to efficient and safe operation

Many IEC TCs (Technical Committees) are involved in the preparation of International Standards that ensure these complex systems work as efficiently and safely as possible. A non-exhaustive list of such TCs and SCs (Subcommittees) includes:

  • TC 17: Switchgear and controlgear
  • TC 20: Electric cables
  • TC 34: Lamps and related equipment
  • TC 47: Semiconductor devices, for sensors and other systems
  • SC 61D: Appliances for air-conditioning for household and similar purposes
Elevator pictogram Elevator pictogram
Escalator in Copenhagen (Denmark) metro Escalator in Copenhagen (Denmark) metro