eRG 21 T hybrid: Innovative hybrid drive reduces emissions by up to 68 %

Powerful combination of 430 kW diesel engine and 88 kW electric motor
Demand-based engine control for optimal power efficiency
Bauer comfort operator cabin, touchscreen with B-Tronic control, integrated power management and basic remote control as standard
Wide range of optional extra features available

Munich, Germany – A construction site with minimal noise and emissions? The eRG 21 T hybrid from RTG Rammtechnik GmbH proves it’s possible. At bauma 2025, the machine was a major attraction at the Bauer booth – and for good reason. Its innovative drive system combines the power of a 430 kW diesel engine with the precision of an electric motor delivering up to 88 kW of additional power (standard power supply: 125 A / 400 V). This unique hybrid technology ensures a constant high level of efficiency, even under strict emission regulations. Thanks to the support of the electric motor, the diesel engine operates with reduced power, which not only markedly reduces noise, but also reduces fuel consumption. As a result, CO₂ emissions are reduced by up to 68% – a remarkable testament to the advantages of this forward-thinking drive technology.

Flexible and powerful

The hybrid drive offers not only environmental benefits but also maximum flexibility. The system seamlessly adjusts between diesel and electric power based on demand, optimizing performance for various applications. When lower power is required, the machine can even operate in fully electro-hydraulic mode. Meanwhile, full power is available for demanding piling tasks.

High-quality standard features

The standard equipment for the eRG 21 T hybrid includes the Bauer comfort operator cabin and a state-of-the-art touchscreen with B-Tronic control. Integrated power management optimizes the use of the hybrid drive. The temperature-regulated fan control system with full automatic operation was specially developed for vibrator operation. Additionally, the machines features a basic remote control as well as retractable side flaps for automatic noise protection.

Optional extras for increased efficiency

A variety of optional features allow customization for specific requirements. An arctic kit or the extended arctic kit plus, for example, enable operation even under extreme weather conditions. An optional second swiveling mechanism increases the swivel braking torque, improving machine control. The energy-efficient power (EEP) system with Eco Mode further helps reduce energy consumption. An extended remote control (Operation) and automatic coupling system for the base machine (ACS I) and all attachments (ACS II) are also available.

Successful use on site

The innovative hybrid drive has already demonstrated its reliability with the eRG 19 T hybrid, the "smaller sister" of the eRG 21 T hybrid. Last year, it was used successfully at the Friedrich-Krause-Ufer site in Berlin. During the special foundation engineering work for a new office and commercial building, the machine executed vibration driving precisely based on a grid pattern, laying the groundwork for an excavation pit with a stable sealing horizon.