Developing emission-free mobile cranes and lifts with a construction machinery pioneer

Wednesday, April 5, 2023

With an extra 2.5 billion people expected to live in urban areas by 2050 and global building floor to double by 2060, cities around the globe are looking to eliminate pollution emanating from construction sites. The construction industry is a significant source of pollution, responsible for 38% of total global emissions as of 2021 and thousands of noise complaints annually. To help countries and municipalities meet their net-zero pledges, the construction industry must quickly decarbonize and adopt carbon-neutral practices.


We started working with Spierings Mobile Cranes, a market leader in construction machinery, in 2016. Convinced by our engineering expertise, comprehensive portfolio, and innovative technology, such as grid connection and micro-grid features, Spierings commissioned us to develop mobile cranes and lifts capable of generating zero emissions.

Powering the world’s first emission-free mobile crane

The first project we undertook with Spierings was the SK487-AT3 City Boy, the world’s first mobile crane powered entirely by electricity and capable of zero-emission operation. With a width of just 2.55 meters and a total length of 13.08 meters, the City Boy is also Spiering’s most compact crane. It is easy to manoeuvre and best suited for operation in urban environments, with a truck footprint of under 10 meters. Small but strong, the City Boy can reach up to 40 meters and lift up to 7 tons with a 1.7-ton tip load.

Powered by an electric permanent magnet synchronous motor driving the first and third axels, the City Boy’s power supply comes from either the battery pack or the diesel generator. The crane is propelled by both energy sources when operating in hybrid mode. Meanwhile, the energy released when the machine is braked is recovered to charge the battery.

In addition to providing the powertrain, comprising an electric motor with a double-sided axle, we also played a significant role in the design of the City Boy. With our input and close collaboration with Spierings, the crane was built so that its energy supply can come from three different sources – fully-electric, diesel generator, or hybrid when travelling or operating.

Electrifying crane operations even further

The release of the City Boy was followed in 2019 by the development of a new eLift solution, for which we provided the components of the electric power pack. Spierings’ eLift can be plugged directly into the grid on a 16A or 32A connection, with the possibility to select a current between 1 and 32A.

The eLift can be operated in either fully electric or hybrid mode. We downsized the diesel engine by half by using an electric motor for power peaks. The hydraulic start/stop system saves up to 90% energy, while diesel consumption can be cut in half – from 6 to 3 liters per hour – when operating the crane in hybrid mode with the electric motor. Additionally, the savings made when lowering the energy needed to run the hoist winch can be used to recharge the battery.

The eLift innovation has been installed on the SK597-AT4 e-Lift, Spierings’ new generation of hydraulic mobile tower cranes with four axels, and on the six-axel Spierings SK1265-AT6 eLift, the world’s largest mobile tower crane. As a result, both cranes can operate fully emission-free.

A step closer toward the total decarbonization of the construction industry

As of 2020, all the machines manufactured by Spierings have electric functionality. Over 150 Spierings machines are now operational with the eLift, which has become a preferred option for customers looking for zero-emission operation and low fuel consumption. The unique solution eliminates local emissions and significantly reduces energy consumption compared to its conventional diesel-powered counterparts by enabling the use of renewable energy through the grid connection. In March 2023, Spierings stopped building and selling conventional diesel cranes, meaning that all of its new crane sales include the hybrid eLift, with an average of two new machines being built weekly.

The company’s City Boy crane is driving emission-free construction and playing a vital role in the decarbonization of the construction industry. Ten machines are currently operating, while Spierings announced the beginning of series production at the Bauma 2022 trade fair.


Project SK487-AT3 City Boy, the world’s first emission-free mobile crane and the zero-emission eLift
Customer Spierings Mobile Cranes
Location Global
Scope Powering and assisting in the design of the SK487-AT3 City Boy, the world’s first emission-free mobile crane, and Spierings’ eLift solution.

City Boy:

Electrified driving and crane operation with flexible power from a battery, diesel engine or the grid.


Electrified crane operation with a versatile power source.

Technical Specificities

City Boy:

  • EC-IDC24 LV power supplies
  • EC-C1200 converters (electric machine control and active front end)
  • EC-LCL1200 filter unit for grid connection
  • Standard EM-PMI375-T800 and EM-PMI375-T1100 machines


  • Standard EM-PMI375-T500 machine
  • EC-C1200 converters (electric machine control and active front end)
  • EC-LCL1200 filter unit for grid connection
  • EC-IDC24 LV power supply. 
  • Zero-emission operation

  • Significantly reduced general energy consumption

  • Lower noise