The focus of the E2Flight 2021 conference is the vision of emission-free flight. For the sixth time, the DLR Institute of Engineering Thermodynamics and the Institute of Aircraft Design at the University of Stuttgart are organising the conference together with Stuttgart Airport. On 25 and 26 February 2021, the online event will provide an insight into all topics relating to electric flight. Experts will report on projects addressing novel aircraft concepts, energy systems and storage, as well as hybrid drives, including their integration into aircraft.
Electric flight with hydrogen and fuel cells
Hydrogen will play an important role in making tomorrow's air transport climate-friendly. Propulsion systems and energy storage systems based on fuel cells operate emission-free. "Hydrogen can be obtained from renewable energies. In combination with fuel cell systems, this green hydrogen has the potential to make emission-free flying possible," explains Josef Kallo, Coordinator of Energy Systems Integration at the DLR Institute of Engineering Thermodynamics.
Together with industry, the DLR Institute of Engineering Thermodynamics in Stuttgart is developing and testing fuel cell powertrains for aircraft. The focus is on increasing their performance. With the Hy4, the DLR spin-off H2FLY has constructed and flown the first four-seater passenger aircraft with hydrogen-electric propulsion. DLR and H2FLY are successfully pooling their expertise to further develop the powertrain. In December 2020, the Hy4 research aircraft received approval for Europe-wide test operations. The Hy4's technology is to serve as the basis for a forty-seat passenger aircraft.
New fuel cell propulsion system with an output of 1.5 megawatts
In the BALIS research project, DLR is going one step further and working on propulsion systems with outputs in the megawatt range. "Fuel cell propulsion systems are particularly suitable for short and medium-haul aircraft with up to 50 passengers and for air taxis. A major advantage here is their high efficiency," emphasises Josef Kallo.
Current fuel cell propulsion systems have an output of approximately 100 to 200 kilowatts. However, it is not possible to combine a number of small systems to achieve a higher total output. “There is a 'sound barrier' at 1.5 megawatts as far as the architecture and performance of today's fuel cell system components are concerned," Kallo explains. "We need to bring together as few fuel cell stacks with as much power output as possible." To achieve this, the DLR researchers want to develop new approaches and components with optimised current densities and voltages.
New forms of propulsion enable new aircraft concepts
In the EXploration of electric Aircraft Concepts and Technologies (EXACT) project, DLR is looking into the integration of propulsion systems based on fuel cells and batteries into aircraft. "Electric flight opens up completely new possibilities for aircraft design," explains Johannes Hartmann, leader of the EXACT project at the DLR Institute of System Architectures in Aeronautics. “The aircraft of the future may look completely different. The propulsion systems can be distributed and installed in the aircraft fuselage and wings in completely different ways.”
DLR takes a whole-system view of air transport. Can alternative propulsion systems be both environmentally friendly and cost effective? What new infrastructure needs to be created, and what infrastructure can continue to be used? How will processes at airports change? "We are developing new technology components for an eco-efficient commercial aircraft. Our goal is to have the necessary components for an aircraft with at least 70 seats and a range of 2000 kilometres ready for use by 2040," explains Hartmann. "Another aspect here is how new types of propulsion systems affect the atmosphere and thus the climate."
You can still register for the online event here.