ThyssenKrupp recently announced they are developing a cable-free elevator system called MULTI that would utilize magnetic levitation technology. According to the company’s press release, “MULTI elevator technology increases transport capacities and efficiency while reducing the elevator footprint and peak loads from the power supply in buildings.”
The world’s first passenger elevator was installed in the E.V. Haughwout Building back in 1857 and it helped usher in the era of the skyscrapers. Today’s elevators are safer, faster and offer a much smoother ride thanks to technological advancements made over the past 157 years, but the core design concept has remained unchanged. A cable is attached on one end to the elevator car and to a counterweight on the other end and looped over a pulley that is powered by an electric motor to lift and lower the car. In the past there have been two major limitations to the modern elevator, the height that an elevator could be lifted and the ability to only travel up and down.
Heavy steel cables used to lift elevators limit the height an elevator can safely travel to about 1640ft (500m) due to their weight and the size of the motor and the power needed to lift them. This is why on taller buildings you have to travel up to a sky lobby and get on another elevator if you want to go all the way to the top. Last year KONE, the Finnish elevator company, introduced UltraRope which features a carbon fiber core encased in a high-friction coating. This new cable weighs 90% less than equivalent steel cables, lasts twice as long, would reduce energy consumption by 15% and would allow elevator cars to travel up to 3,281ft (1km), twice the distance of the current maximum effective height.
The UltraRope technology will be used in the Kingdom Tower building currently under construction in Saudi Arabia which is expected to be the tallest building in the world when completed, reaching a height of 3,281ft. The building will use UltraRope to achieve the world’s tallest elevator rise at 2,165ft and feature the world’s fastest double-decker car that will travel at 22mph.
By completely eliminating the use of cables to lift and lower the elevator car, ThyssenKrupp’s MULTI will mean elevators be able to reach heights far beyond those allowed by KONE’s UltraRope technology. In addition to freeing elevators from any height limits they can reach, it would also free them from the restriction of only being able to travel in two directions, up and down. The technology will allow elevator cars to run horizontally as well as vertically and for multiple cars to operate in each shaft.
The MULTI will use the same magnetic levitation linear motor technology used in the Transrapid Shanghai Maglev Train. Transrapid International is a joint venture between ThyssenKrupp and Siemens. The control systems and safety features for the MULTI will be based on ThyssenKrupp’s TWIN elevator system which allows two elevator cars to operate independently of each other in the same elevator shaft. The self-propelled elevator cars will feature a multi-level brake system and inductive power transfers from the elevator shaft to the individual cars.
The question remains as to whether or not this new technology will transform the way buildings are designed and used. The unobstructed mobility provided by a maglev elevator that can travel up, down and sideways could lead to new shapes and sizes not currently seen. It’s a shame they aren’t working on an elevator that can go slantways.
The cars would travel at 11 mph in a loop which would mean passengers could have access to a car every 15 to 30 seconds depending on the configuration and number of cars. The MULTI is expected to be tested in 2016 at the company’s new test tower currently being constructed in Rottweil, Germany.