New sensor technologies cut operating costs

However, outdated sensor systems result in inefficiencies in the lift sector, which is reflected in annual maintenance costs of 20 billion USD, delays in installation, higher labour costs and inefficient energy use.

By Beat De Coi

The global lift sector has an estimated market value of over 100 billion USD and an annual growth rate of 4.8 percent but is faced with growing challenges in terms of safety, efficiency, installation costs and maintenance. What is needed are solutions for real-time passenger counting, obstacle recognition, predictive maintenance and lift automation.

By means of innovative sensors, energy savings of up to 25 percent, maintenance cost reductions of up to 40 percent and enhanced passenger safety are possible – an outlook on the future of the vertical transport (also see: De Coi, B. 2025, Elevcon 2025: Innovative Sensor Solutions Using Optical Semiconductor Technology).

Considerable action is still needed

Beat De Coi. Photo: © Espros

Urbanisation is continuing to drive the demand for lifts. Over 20 million units are in operation worldwide and about seven billion trips are carried out daily. However, outdated sensor systems result in inefficiencies, which is reflected in annual maintenance costs of 20 billion USD, delays in installation, higher labour costs and inefficient energy use.

These challenges have admittedly been addressed in detail in the past – especially by means of improved standards – but considerable action is still needed. A volumetric sensor, a "fill level sensor" so to speak, could contribute to enhancing the energy efficiency of lifts.

A study from 2005

In the course of this study, a simulation was performed regarding how the efficiency of a lift could be improved by means of a volumetric sensor. The sensor measures the occupied floor space in the car. What needs to be understood is that this measurement cannot be replaced by load sensors since people with luggage have a lower specific area load than people without luggage.

A typical passengers occupies about 0.22 m2 floor space in the case of maximum occupancy, which corresponds to just 0.5 × 0.5m, which is extremely cramped. In practice, each person takes up about 0.5 m2 (about 0.7 × 0.7 m), which means the effective capacity of a lift is usually clearly below the theoretical. In addition, cleaning staff with bulky equipment take up additional room, which causes a further reduction in the specific area load.

The study’s authors calculated the time saving per passenger based on factors such as the number of floors, lift-specific parameters and other numerical assumptions. A typical scenario where an intelligent volume sensor is advantageous is for example a business hotel at checkout time: a brief but intensive time window with a high traffic volume. Here a volume sensor helps to avoid unnecessary stops of cars whose space is already full.

Gain in efficiency and energy saving

The result of the study: a reduction in waiting times by about 50 percent thanks to the application of volumetric car occupancy measurement. This reduction can be converted directly into energy savings since unnecessary stop and start-up procedures are reduced. The gain in efficiency is achieved primarily from energy being saved when accelerating and decelerating the car.

For example, in a 20-floor building lifts cause annual energy costs of about 16,000 euros. These costs could be slashed. Energy savings potential results in particular during the deceleration processes, door movements, acceleration and idle times through lighting, ventilation, etc. Given an assumed energy consumption of 0.1 to 0.2 kWh per unnecessary stop and 300 stops a day, this involves an annual waste of energy from 10,000 to 20,000 kWh per lift. In addition, the wear, especially for the doors, is greatly reduced.

 
Source: Espros

Conclusion

A simple, affordable 3D volume sensor can cut the annual operating costs of a lift by several thousand euros through the reduction in unnecessary stops.

More informations: https://www.espros.com/

The author is the Chairman of Espros Holding und Chairman of the Board of Directors at Espros Photonics. Among other things, the company produces 3D volume sensors.