WP6-Brochure-E4 brochure - ELA European Lift Association.

It is evident that the way lifts are controlled has a major impact on energy consumption. By
efficiently delivering passengers with the least amount of trips, starts and stops, and number
of lifts used, the energy consumed is significantly reduced. Also, less effective traffic
controllers, causing longer waiting times, can lead to the improper use of the system by
impatient passengers (e.g. pushing both up and down buttons), further degrading the quality
of the service.
Provided passenger’s waiting times are kept within reasonable limits, the energy consumed
should be minimised. A number of different strategies can be engaged to achieve this purpose:
• Shut down lifts during periods of low traffic demand
Lift groups are designed to respond optimally to heavy traffic demand situations, such as
during up‐ or down‐peak demand. During interfloor traffic, the capacity of the installation is
never fully used. Therefore, it may make sense to disable some of the lifts in the installation
during this low demand periods, without significantly affecting the system’s traffic handling
performance. This would by itself produce considerable energy savings, but it has one side
effect that further enhances the energy efficiency of the installation. By reducing the number
of lifts in use, the car load is increased, moving closer to the counterbalancing ratio.
• Appropriate zoning arrangement
In high‐rise buildings, it is possible to group the lifts to serve particular zones of floors. This
creates the need for people travelling to floors within that zone to use the same lifts, thereby
reducing the number of start / stop cycles made and avoiding unnecessary energy losses.
Appropriate zoning arrangement will not only improve the energy performance of the lift
installation, but it will also improve the handling capacity and the quality of the service due to
a shorter Round Trip Time.
• Use of advanced algorithms
Employing advanced algorithms that track where each lift is located, to consider the potential
energy available from its car and counterweight locations.
• Monitoring Devices
Modern controllers have logging capabilities which are indispensable for maintenance
purposes. They register data related to failures, but can also provide additional data that can
be used to improve the performance of the system. By logging information on the energy
consumption of lifts a means of conducting energy audits is also provided. The availability of
information improves the awareness of building owners / managers on the electricity
consumed by the system. This information may also be combined with other information
logged by the controller (e.g. traffic patterns, idle times, and load) and used to improve the
energy performance of the installation.
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