TK Elevator celebrates twenty years of TWIN

The remarkable TWIN elevator uses two cabins – moving independently in one shaft – to safely transport more passengers in fewer elevator shafts, thus freeing more rentable space at reduced construction cost and energy consumption. TK Elevator salutes the 20-year anniversary of this unique form of urban mobility – and the continuing digital evolution of sustainable buildings and cities.

The value of innovation

Twenty years ago, TK Elevator unveiled a new and ground-breaking type of elevator – TWIN – at The University of Stuttgart (Germany). What made TWIN so revolutionary was that it was the world’s first elevator to have two cabins independently operating in the same shaft. This meant that TWIN was capable of transporting up to 40% more passengers, while requiring 25% less of a building’s valuable floorspace than conventional elevators. Initially thought as solution for ‘underlifted’ buildings or buildings where its utilization purpose changed over time, the TWIN solution was easily identified as flag ship product as well for new buildings giving customers much more architectural freedom and this all with much less elevator shafts necessary as for conventional solutions.

Elevator World immediately recognized the significance of TWIN with a Project of the Year Award in 2003. Owners realized that they could save a significant amount of energy used in their buildings – TWIN provides a cost-effective way to be more sustainable. And developers realized that having fewer shafts meant more leasable space and lower costs – TWIN makes buildings more attractive to investors.

Hudson Yards in NYC

Built-in flexibility

Twenty years later, TK Elevator’s TWIN is still the only elevator company in the world capable of offering the many benefits of two cabins moving independently in one shaft. Another group who immediately understood the advantages of this were architects and project developers. For instance, they realized that they no longer needed to have identical floor to floor distances bs – TWIN opens up new design concepts, much lighter entrance halls and more architectural freedom.

Double-decker elevators were already in use when TWIN hit the market. These trusty workhorses are truly powerful people-moving tools, but what they do best is to move a lot of people to two adjoining floors – of the same height – and both cars can operate only simultaneously. This can lead to irritation for the passengers because of ‘phantom stops’, when passengers load or unload at only one car, the other car has always to wait. Architects have already a lot of constrains to solve in their daily work, sometimes need to design buildings with varying floor heights. In those cases, greater flexibility is needed.

TWIN provides that flexibility, as well as ensuring better inter-floor connectivity in any high-rise building.

Amazing TWIN elevators cars operating in an atrium at St. Botolph office building, UK

Anticipating the digital age

A benefit more immediately obvious to passengers is what happens when there is a “rush hour” in the building. Here, TWIN clearly displays the advantages of TK Elevator’s digital expertise in people-moving technology. Whereas passengers traditionally crowd into lobbies and struggle to get onto the first elevator to arrive, TWIN civilizes the process, opens up to double as much lobby spaces without losing rentable square meters and minimizes congestion and waiting-times.

The reason why TWIN is able to provide such streamlined passenger mobility is that it was created with the digital future in mind. Passengers simply select a destination floor at an AGILE – Destination Control lobby terminal. The intelligent advanced dispatching algorithm collects and analyses this information, gauges traffic demand and automatically indicates passengers the elevator which will be best suited to reach the desired floor fastest.

TWIN’s ‘agile’ digital brain not only quickens the pace and improves efficiency, it also allows for adaptability to brand-new building traffic concepts. Indeed, although the idea of using two cabins in one shaft had been described and patented around 1930 as a futuristic idea, it was only when TK Elevator applied state-of-the-art engineering, the right software for controlling both elevator cars in one shaft and state of the art digital design to the task that TWIN’s innovative solution emerged, and the full potential of the idea was finally realized.

Smart software at the heart of the TWIN system is also part of the reason why TWIN is clearly one of the safest elevator systems in the world. TWIN boasts a four-step, TÜV-approved and SIL3-classified safety system, which ensures that the cabins always operate at a minimum safety distance from one another. TWIN’s safety system has never failed – exactly what you would expect from safety-conscious TK Elevator.

Step 1: Passengers use the terminal to select their floor. You can add custom button labels and logos to make the process even easier.

Step 2: AGILE terminal clearly directs each passenger to an assigned elevator.

Step 3: Passengers board the assigned elevator that transports them to their destination.

Smart getting smarter

And because smart software just keeps getting smarter, TWIN has flexibly adapted to that, too. More than a decade after TWIN was launched, TK Elevator rolled out MAX: the world’s first real-time, cloud-based predictive elevator maintenance system. MAX integrates machine learning, Internet of Things (IoT), Big Data and cloud technologies, and applies them to mobility maintenance. This significantly reduces breakdowns, increases uptime, and generally optimizes building operations. TWIN now comes equipped with MAX. And MAX is ready for the next digital wave, too.

Sustainable design – using less, getting more

TK Elevator’s digital engineering also helps make TWIN more energy efficient: saving a significant amount of the energy used in a building. For example, TWIN conserves energy by parking one of the cabins whenever passenger volumes are low. That means immediate savings for owners, as well as long-term benefits for the environment. The energy consumption of buildings is one of the largest contributors to the operational carbon footprint of cities around the world.

And TWIN’s sustainability credentials have been strong even in its early times: the system is equipped with an advanced regenerative drive. This ingenious invention uses the elevator’s own braking mechanism to actually generate electricity, and feeds that unused energy back into the building. Using less energy is good for the planet, and for the building’s bottom line.

Happy to be a team player

With its overall versatility and dependable digital connectivity, TWIN also works perfectly well in combination with other types of elevators. This is of particular interest for the growing number of high-rise buildings, which often need to seamlessly coordinate a variety of mobility solutions.

For buildings with more than 35 landings, for instance, designers usually use a sophisticated configuration of devices that may include everything from regular elevators and escalators to express elevators, multiple access areas, modern double-deckers, and TWIN systems. AGILE – Destination Control ensures that traffic flows evenly, which keeps passengers content. TK Elevator manufactures models in all of these categories, and can easily assist planners in achieving the optimal transporter configuration for the needs of their building.

Rejuvenating legacy high-rises

As of 2023, there are more than 1,000 TWIN elevator cars in service in buildings all around the world. Many buildings cleverly incorporated TWIN into their original design. Others chose TWIN as part of an ambitious modernization plan. TWIN’s built-in benefits bring older buildings up-to-date by providing greater mobility, as well as energy efficiencies, cost-saving predictive maintenance and personalized digital passenger services. TK Elevator’s TWIN is breathing new life into an increasing number of older skyscrapers, as well.

Moving people and opening minds

TK Elevator knows that sustainable buildings and cities are the only desirable way forward for humanity. Continuing urban growth is simply a fact – and we must manage it well to fully reap the benefits. Happily, the explosion in digital technology offers an expanding range of tools that we can use to do that. TK Elevator’s mission is to investigate and develop every applicable technology, to dream boldly about human mobility, and then to use that combination of knowledge and vision to create solutions that perform well, thus expanding the understanding of others – planners, architects, developers, passengers – of what is possible.

Celebrating twenty years of TWIN

TWIN is a superb example of TK Elevator’s vision in practice: a ground-breaking innovation in the technology of human mobility, and an opportunity to move beyond conventional ways of transporting people. Which we will all have to do more of – to create a more mobile future.

TWIN early adopters

Here are a few of the buildings using TWIN elevators:

  • St Botolph Building, London, UK – TWIN elevator systems reduced space needed for the elevators by 2,700 m² (29,000 square feet) – an increase of 6% in leasable space. The 13-floor office building houses eight TWIN elevators.
  • Trinity Tower, Paris, France – The fantastic 33-floor elevator display gives passengers an unparalleled view over the city’s La Défense business district, and reduces their waiting times by up to 30%. Awarded: Project of the year 2022
  • Hudson Yards, New York City, USA – Connecting the largest private real estate development in U.S. history, TK Elevator is supplying 16 TWINs, 9 double-deck and 54 single-deck elevators as well as 12 escalators.
  • European Central Bank Headquarters, Frankfurt, Germany – TWIN helps the ECB meet its sustainability goals: Energy efficiency was a core tenet of the building’s design.

TWIN – Cleverly designed by TK Elevator to be ready for whatever comes next.

TK Elevator’s dedication to innovation means that TWIN now comes factory-equipped with regenerative drives for greater sustainability, cloud-based MAX predictive maintenance software, and future-ready capabilities for digital enhancements.

Would you like to know further details? Contact us!

Get in touch with us via our contact form to receive either the fantastic whitepaper from 50 Hudson Yards, NYC, project with insights from its architect, Lord Norman Foster, or our white paper on traffic simulation for high rise buildings to learn more about the optimal elevator portfolio for a smooth flow of people.