Leeham News and Analysis
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Leeham News and Analysis
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- Boeing CEO promises company is turning around…again April 24, 2024
- Solid start for stand-alone GE Aerospace despite cuts to LEAP output April 23, 2024
- SPEEA, Boeing at impasse over safety program, union says April 23, 2024
- Better transparency needed on Boeing’s 1Q earnings call April 22, 2024
The true cost of Electric Aircraft. Part 2.
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By Bjorn Fehrm
Introduction
July 8, 2021, © Leeham News: Last week, we looked at the cost of running an electric 19 seat airliner based on energy stored in batteries. We found the energy costs were lower than for the equivalent turboprop aircraft, but when we add the maintenance costs for the batteries, the operating costs were higher than today’s 19 seat commuter.
This was under the assumption that the battery aircraft had the same energy consumption as today’s aircraft. We now run this check. The result is eye-opening.
Figure 1. Heart Aerospace ES-19 battery-based airliner. Source: Heart Aerospace.
Summary
- Battery based aircraft weigh significantly more than jet fuel based ones. It increases their energy consumption.
- Last week’s findings were conditioned on the same energy consumption. This week’s analysis proofs this is not a valid assumption.
Bjorn’s Corner: The challenges of hydrogen. Part 33. Wrap-up: The Eco-system
By Bjorn Fehrm
April 16, 2021, ©. Leeham News: Last week, we wrapped up the operational part of sustainable air transport using hydrogen as an energy source.
Now we look at where we are with the all-important Eco-system. It has many moving parts and risks a chicken and egg stalemate.
Figure 1. The prospective conversion of the European gas pipeline network to hydrogen. Source: EU.
Bjorn’s Corner: The challenges of hydrogen. Part 32. Wrap-up: Going forward
By Bjorn Fehrm
April 9, 2021, ©. Leeham News: Last week we made a summary of the history of initiatives for sustainable aviation, now we look at the likely developments over the next 10 years.
What is the likely development for different classes of airliners and what technologies will be popular?
Bjorn’s Corner: The challenges of hydrogen. Part 31. Wrap-up: Where we stand
By Bjorn Fehrm
April 2, 2021, ©. Leeham News: It’s time to wrap up our series on the hydrogen airliner alternative for Sustainable Commercial Aviation.
We review the status for sustainable aviation as of today, then look at the future next week.
Figure 1. The first certified electric aircraft, the Pipistrel Velis Electro. Source: Pipistrel.
Bjorn’s Corner: The challenges of hydrogen. Part 30. Integrated nacelles.
By Bjorn Fehrm
March 26, 2021, ©. Leeham News: This week, we look at combining the propulsion and hydrogen tank in an integrated nacelle as Airbus proposes in Figure 1.
Airbus calls it its “pod” solution. What are the advantages, and what challenges does it present?
Figure 1. Airbus concept for a turboprop with integrated nacelles. Source: Airbus.
Bjorn’s Corner: The challenges of hydrogen. Part 29. Gas turbine heat management.
By Bjorn Fehrm
March 19, 2021, ©. Leeham News: This week we look deeper into the gains we can have for a hydrogen gas turbine-propelled airliner.
The ideas stem from the work of Chalmers Professor T. Grönstedt’s team in different EU research projects.
Figure 1. Gas Turbine heat management as presented in EU ENABLEH2 project. Source: ENABLEH2.
Bjorn’s Corner: The challenges of hydrogen. Part 28. Airbus priorities
March 12, 2021, ©. Leeham News: I had the chance to talk about Sustainable Air Transport with Airbus VP Zero Emission Aircraft, Glenn Llewellyn, in the week.
The discussion centered around Airbus’ overall direction and the targets with their ZEROe project.
Figure 1. Airbus ZEROe airliner concepts. Source: Airbus.
Bjorn’s Corner: The challenges of hydrogen. Part 27. Fuel cell APU gains
By Bjorn Fehrm
March 5, 2021, ©. Leeham News: We have discussed different auxiliary power generation principles for a hydrogen aircraft over the last weeks. We found a fuel cell auxiliary power system has many attractions, one being the possibility of making an elegant more-electric aircraft system architecture.
With or without such an architecture, the fuel cell alternative will save hydrogen consumption and cost compared to a hydrogen-converted APU alternative. What’s the value of the saving?
Figure 1. The Ballard/Audi FCgen-HPS fuel cell stack for cars and other mobility applications. Source: Ballard Power Systems Inc.
Bjorn’s Corner: The challenges of hydrogen. Part 26. Auxiliary power
February 26, 2021, ©. Leeham News: Last week we discussed auxiliary power generation for a hydrogen aircraft and found that a fuel cell system had many attractions.
However, it’s more challenging to develop than a hydrogen-converted APU, and we were asked to work through this case as well.
Figure 1. The principal parts of a single-aisle APU. Source: United Technologies.
Bjorn’s Corner: The challenges of hydrogen. Part 25. Auxiliary power
By Bjorn Fehrm
February 19, 2021, ©. Leeham News: Last week we discussed hydrogen aircraft propulsion and found a shaft power producing gas turbine was considerably more weight-efficient than a fuel cell powering an electric motor. Both had the same 55% shaft power efficiency.
Will a gas turbine APU burning H2 be the best choice for auxiliary power as well?
Figure 1. The Honeywell 131-9 APU for the Airbus A320. Source: Honeywell.