David Noel
<davidn@aoi.com.au>
Ben Franklin Centre for Theoretical Research
PO Box 27, Subiaco, WA 6008, Australia.
DS913: The Rotalift, a more efficient alternative to elevators and other lifting devices
A new approach to elevators and other lifting devices
Everyone in the modern world is familiar with elevators or lifts in multi-storey buildings, all new buildings with 4 or more floors are designed to include them. In addition, there are many other industrial processes, such as mining, which may involve the lifting of large amounts of materials.
Those who rent in multi-storey buildings will know that the inclusion of elevators may drastically alter the conditions and costs involved. It's impractical in modern times to expect users of buildings with more than 3 levels to make use of stairs alone to access the different levels.
Now a new alternative to conventional elevators, the Rotalift, has been devised, which incorporates two techniques proven from other areas. These should dramatically improve the efficiency of lifting devices of many types. The two proven techniques are Magnetic Levitation, as used in the Shanghai Airport Maglev train, and Flywheel Energy storage to power vehicles, as with some Swiss bus services.
Figure DS913-F1. The RotaLift.
Figure F1 is a rather poor diagrammatic overview of the items involved. These include a lift body (here a circular passenger carriage, though squarer shapes would be possible) with power and traction components, and a double-helix track to support the lift in its movements up and down.
Before going into details of the RotaLift, let us look at the technologies involved as they have been developed in other areas of engineering -- first, the Magnetic Levitation Train.
The Maglev Train
The best-known Maglev Train is that running between Shanghai's city centre and its airport. It was opened in 2004 [1]. By 2025, there were 7 maglev trains in public operation (four in China, two in South Korea, and one in Japan).
Figure DS913-F2. The Shanghai Airport Maglev Train. From [1].
Maglev is a system of rail transport whose rolling stock is levitated by electromagnets rather than rolled on wheels, eliminating rolling resistance [2].
Compared to conventional railways, maglev trains have higher top speeds, superior acceleration and deceleration, lower maintenance costs, improved gradient handling, and lower noise. However, they are more expensive to build, cannot use existing infrastructure, and use more energy at high speeds [2] .
Maglev trains use magnets in two ways. First, permanent or electromagnets in the guideway (track) and in the train are activated with like poles (south or north) in proximity, the resultant repulsion pushing them apart so the train floats 1 to 10 cm above the solid surface.
Figure DS913-F3. Magnetic levitation and propulsion. From [3].
Second, the train is moved forward by activating magnets of opposite polarity, so north and south poles attract and move the train in the desired direction. This is technically a linear motor, like a normal electric motor unrolled flat.
Flywheel-powered vehicles
Vehicles powered by flywheels have been in successful use for many years. A Swiss bus service was operated in which bus flywheels were spun up at the terminus or halt stations, this had vehicles capable of travelling up to 10 km between charges.
Figure DS913-F4. Loading up the bus flywheel with three-phase charging. From [4].
There is a more detailed examination of flywheel-powered vehicles in DS903: The KPW (Kilogram Power Wheel): A domestic power storage device replacing batteries [4] .
Flywheels of one sort or another have some notable advantages over batteries as sources of power. Power stored in a battery is limited by electrochemical considerations, this power has a theoretical maximum which cannot be exceeded. Power in flywheels depends on rotation rate, which has no theoretical limit. Moreover, power storage increases as the square of rotation rate --a flywheel rotating at twice the rpm (revolutions per minute) has four times the energy,
Back to the RotaLift
The RotaLift design shown in Figure F1 uses both the Maglev Train principle and the stored-energy flywheel concept to give a lifting or elevator device which should be markedly more energy-efficient than contemporary methods using cables driven by electric motors.
Figure DS913-F1. The RotaLift.
At the centre of the design is a conventional passenger cabin or material container. Above and below this are the RotaFlies, energy-storage flywheels of conventional or possibly highly-improved design.
Only one RotaFly is actually needed, but having two RotaFlies, rotating in opposite directions, gives more flexibility in power draw and limits possibly unwanted gyroscopic effects.
Shown notionally above and below the RotaFlies are the RotaYokes, possibly annular bands which can rotate relative to the cabin. These RotaYokes are connected to Yoke Arms which terminate in Shoes resting on the upper RotaTrack surfaces. Actual implementations would probably have the Shoes running in a trench, as in Figure F3.
The RotaTracks are a pair of helical guideways, possibly of reinforced concrete, capable of bearing the weight of the cabin, and containing the necessary magnet sets to enable the Shoes to float above the track solid surface.
In operation, the magnet sets are activated so that the RotaLift Shoes travel up or down along the guideway troughs, thus moving the Lift up or down. The Cabin is restrained from rotating in the lift shaft, either mechanically (as with a guide rail) or electronically.
Energy Considerations
Rotalifts should be far more energy-efficient than conventional lifts. The latter typically have cabins raised or lowered by cables winding onto cable drums. Considerable energy is drawn in raising the cabin to upper levels, and most of this is lost to braking when the cabin is lowered.
With the RotaLift, most of this energy is recovered by regenerative braking and stored in the RotaFlies as the RotaLift descends. This contrasts with energy lost to frictional brakes in conventional lifts.
The RotaLift also has minimal energy losses to friction, as the Shoes float above and are not in contact with the Guideway troughs. In theory, a passenger Rotalift operated over a day in a tall office building would be energy-neutral, as the same number of passengers would be lifted (drawing energy from the Rotaflies) and lowered (feeding energy back to the flywheels),
In practice, there would be some frictional losses as the Yoke Arms rotated slowly relative to the cabin, and with the guide rail governing this, if installed. With Maglev Trains, an appreciable source of energy loss is with air resistance at high speeds, this would not apply to RotaLifts.
Safety Considerations
RotaLifts should offer better inherent safety than conventional lifts. There are no cables to break or mechanical brakes to fail. If the building should lose power, the RotaLifts would still have their inbuilt power in the RotaFlies, to operate lift doors and perhaps limited motion.
In the worst case of a major disaster, such as an earthquake causing a building to tilt out of alignment, and the RotaTracks crumbling, the Rotalift should still settle gently on its guideways.
In common with Maglev Trains, RotaLifts would be protected from derailment from their guideways because the forces acting on them themselves force the vehicle into place.
Other advantages
Because the RotaLift design does not incorporate cables, a lift run could be of any height or depth. At present, very tall buildings (or deep mines) may need to break up lift runs into sections, because of limitations on winding long cables.
Development of RotaFlies
Rotational methods of power storage are capable of considerable development, well beyond battery-power possibilities. Having flywheels magnetically levitated, and operating in a vacuum, would virtually eliminate fractional losses.
Another possibility is that of the Power Torus. In this, the flywheel is replaced by an electromagnetically-controlled spinning torus (the axle is eliminated from the flywheel) as in Figure F5.
Figure DS913-F5. The Power Torus concept.
These concepts are examined in more detail in DS903: The KPW (Kilogram Power Wheel): A domestic power storage device replacing batteries [4]. The concept of crawling lifts powered by flywheels was covered in SC007: The Birdcage, A World Tourist Icon for Perth, Western Australia [5].
* * * * * * * * * * * * * * * * * *
References and Links
[1]. Shanghai maglev train. https://en.wikipedia.org/wiki/Shanghai_maglev_train .
[2]. Maglev. https://en.wikipedia.org/wiki/Maglev .
[3]. How Maglev Works. https://www.energy.gov/articles/how-maglev-works .
[4]. David Noel. DS903: The KPW (Kilogram Power Wheel): A domestic power storage device replacing batteries. ww.aoi.com.au/devices/DS903/ .
[5]. David Noel. SC007: The Birdcage, A World Tourist Icon for Perth, Western Australia. www.aoi.com.au/social/SC007/ .
* * * * * * * * * * * * * * * * * *
Go to the Devices Home Page
Version 1.0 began assembly 2026 Jan 14. Version 1.0 on Web, 2026 Jan 28.
