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According to Wikipedia, the Rolls Royce "Spirit of Innovation" is based on the Sharp Nemesis NXT aircraft and uses HARTZELL 3 blade propellers. The Sharp Nemesis kit based, all composite aircraft is capable of speeds in excess of 400 mph.
To get a proper perspective of this aircraft look at the blueprint on https://www.rolls-royce.com/innovation/accel.aspx#motors. The tail assembly does not appear to be large in proportion to the overall aircraft design. As far as propeller size, Rolls Royce probably knows a lot more about airfoil design than most of us. Also, you could look at one of the fastest propeller aircraft of all time, the Focke Wulf Ta 152 H-1 which had a top speed of 472 mph with GM-1 Nitrous Oxide injection for use at high altitude. The nitrous TA 152 H-1 has a 3 blade, relatively small propeller.
This is the third new Nissan IC engine introduced in the past two years (PR25DD I4 2.5 L Direct injection, the Variable Compression Turbo I4, and this one)! The Qashquai Crossover SUV has a standard model with a 138 hp 1.3L DIG-T turbo and can be upgraded to a variable compression ratio 1.5L turbocharged gasoline engine with an electric motor that delivers a total of 184bhp and 330Nm of torque (in front-wheel-drive only). What Nissan needs to do is take this new engine and add the Mitsubishi AWD PHEV system with > 200hp. BTW, my everyday drive is a 40 mile range Nissan Leaf (don't worry it was free and takes care of 90% of my driving).
Oshkosh Defense is being very quiet about the powertrain and the supplier. Ford was a partner and the prototype was a Ford Transit Van. Ford could supply the internal combustion engine (a 2.5L I4 Atkinson Cycle engine?) and the Chassis (like the F59 E350 Chassis). However, the battery and electric motor systems probably are Oshkosh based. Microvast looks like the the battery cell supplier (https://www.electrive.com/2021/02/11/microvast-to-build-plant-and-work-with-oshkosh/) and the electric motor system may be based on the Oshkosh Pro-Pulse series hybrid modular drive. More details should come out soon.
FWIW Electrify America (a subsidiary of Volkswagen Group of America) actually has charging stations across Canada, though it is called Electrify Canada.
Tesla acquired a company called SilLion that embeds Silicon nanoparticles in a cyclized-polyacrylonitrile (cPAN) conductive fiber network. This low cost approach was revealed at the "Tesla Battery Day" last year. Possibly, this self-healing polyborosiloxane (PBS) coating can improve on the Tesla Anode. Already, a small percentage of Silicon is added to Anodes (5%), these methods could increase that to >25% at little additional cost. References: " The Highest Energy Li-ion Battery: Unlocking the Potential of the Silicon Anode and Nickel-rich NMC Cathode", Dr Daniela Molina Pipe, Dr Tyler Evans, https://www.scientia.global/wp-content/uploads/2017/08/SiILion.pdf "Hierarchical Porous Framework of Si-Based Electrodes for Minimal Volumetric Expansion", DOI: 10.1002/adma.201305781, http://engineering.snu.ac.kr/pdf/2014(15)/2014_DMP_Hierarchical%20porous%20framework%20of%20Si-based%20electrodes%20for%20minimal%20volumetric%20expansion.pdf.
Good Points Mahonj, Siemens has been testing the eHighway since 2017, so long trucks and buses could use this dual-mode battery-catenary concept (Check:https://press.siemens.com/global/en/feature/ehighway-solutions-electrified-road-freight-transport). ABB has "Opportunity charging for electric buses" where high power charging via an automated rooftop connection with chargers at endpoints, terminals and intermediate stops. Typical charge times are 3 to 6 minutes. (https://library.e.abb.com/public/c09e6e5078914efe874925c24b56f772/ABB_EVI_ProductLeaflet_HVC-OpportunityCharging_nd_web.pdf).
Waltersteffe1, To understand Energy Density (both Gravimetric and Volumetric) you need to look at the "Total System" or specific Transportation Vehicle. Let's look at two components: the Powerplant and Fuel Fraction. Powerplant efficiency varies whether you look at Hybrids, Atkinson Cycle, Diesel Cycle, Brayton Cycle, Fuel Cell, or BEV. A heavy, diesel Semi Class 8 truck that needs to travel over 700 miles on a tank of fuel needs at least 500 Wh/kg Powerplant Energy Density. (a BEV might take it 600 miles), Diesel efficiency >40%. A Commercial Airliner that has to travel 5000 miles like a Boeing 787 needs a "Fuel Fraction of 40% and has efficient GENx Turbofan engines (>42%), is really getting close to that "46.4 MJ/Kg" Energy Density requirement. This is the reason I stated that "Drop-in JP8 Renewable Fuel" is the only reasonable clean alternative. While Liquid Hydrogen could work, it is expensive (unless made from Natural Gas) or still has poor Volumetric Energy Density.
Waltersteffe1, You can read in my earlier post on the Fraunhofer Whitepaper (like Davemart says) that this is based on: "At an efficiency of ~ 0.17. Conversion with an internal combustion engine of a 1 kW system under realistic load changes." Check "Engine Efficiency" on Wikipedia or other sources, and the average internal combustion engine efficiency is around 20%, subtracting mechanical losses and 17% is reasonable. Forget 46.4 MJ/Kg, the only way to get that much energy is to light a match!
Two more references for POWERPASTE. 1. Explains the 2.3kWh/kg (recycling FC H2O output), "Hydrolysis of Mgh2 For ultra high energy applications", https://www.energysaxony.net/fileadmin/Inhalte/Downloads/Pressemitteilungen/Pressefaecher/Fraunhofer_IFAM/alt/hydrolysis_of_MgH2_for_ultra_high_energy_applications_fraunhofer_ifam_dresden.pdf. 2. PowerPaste for infrastructure-independent hydrogen and energy solutions, https://www.youtube.com/watch?v=E7-i0dzx1Ho. Probably, looks like 1600 Wh/kg is combined MgH2 + H2O.
Have not seen a specific reference to component weights (MgH2 and H2O). Did notice a comment on the Fraunhofer web site (https://www.ifam.fraunhofer.de/de/Institutsprofil/Standorte/Dresden/Wasserstofftechnologie/hydrolyse.html) that states:"If water is available, gravimetric energy storage densities of more than 2.3 kWh / kg can be achieved - including all conversion losses - which corresponds to a gravimetric hydrogen storage capacity of approx. 15% by weight ." Will continue to research your question.
Long range commercial aviation can use low NOx, Drop-in Renewable JP8 fuels. Fraunhofer is not going to compete with Toyota, Mercedes Benz, and the German government on mature tech Class 8 FCEV Compressed H2 trucks. So here are some specs for a Scooter/Moto based on the very good Zero ZF7.2 eMoto. Current Specs: 34 kW, 7.2 kWh battery(weight around 40 kg), Range: 91 miles, Cost:$11k. POWERPASTE eMoto: 8 kW Fuel Cell (4 kg weight), 1.2 kg POWERPASTE canisters (12.5 kg), Guoxuan High Tech JTM LiFePo battery (cheap as PbA, 14 kg). Total Energy store weight= 30.5 kg. Range (based on 19.2 kWh H2) = 243 miles.
Maybe a real Hydrogen EBike may help you visualize what can be accomplished with this H2 Storage. Professor Kondo-Francois Aguey-Zinsou built a hydrogen powered eBike in 2014 using Hydride storage. (Read here: "Australia's first fuel cell bicycle", https://phys.org/news/2014-09-australia-fuel-cell-bicycle.html). This eBike Specs were: Battery: 518 Wh Lithium-ion battery, Fuel cell power: 100W, Canister: 738 Wh capacity. Fraunhofer has in a test environment used 300 W Fuel Cells which could charge a 1kW battery (PowerDensity). Larger Fuel Cells, e.g., 750 W could charge a 2.25 kW battery/electric motor system. The problem is where do you get a POWERPASTE canister outside Fraunhofer? Professor Kondo-Francois Aguey-Zinsou solves this with a "Hydrogen Battery" (the LAVO system has a FC and electrolyzer). A Unitized PEM Regenerative Fuel Cell would be a better solution. You can read some recent research here: "A Novel Stack Approach to Enable High Round Trip Efficiencies in Unitized PEM Regenerative Fuel Cells" (https://www.hydrogen.energy.gov/pdfs/review20/fc331_ayers_2020_p.pdf).
Costs are probably the biggest concern (the LAVO system costs $35,000 AUD). So low cost transportation BEV probably is the best approach. Long range applications. e.g. trucking, ships, air which also have expensive powerplants would be better.
Hydrogen production or discharge rate should not be a problem. Higher rates can be achieved by multiple storage tubes for example. Also, Metal Hydrides have already been used in submarines (Howaldtswerke-Deutsche Werft GmbH U212) and grid applications (Toshiba H2One). However, these were low density Lanthanum MIschmetal Nickel alloy H2 storage. There have been other projects that have used Magnesium Hydride (Check: "Application of hydrides in hydrogen storage and compression: Achievements, outlook and perspectives", Volume 44, Issue 15, 22 March 2019, Pages 7780-7808 - https://www.sciencedirect.com/science/article/pii/S03603199193023680).
Metal Hydrides look like the next step in Fuel Cell Tech, even though they have been working on this for over 40 years! Power density should not be a concern since the discharge rate looks good enough to drive large fuel cells. It appears that the Fraunhofer Institute for Manufacturing Technology and Advanced Materials does not want to compete with Compressed H2 (read here: https://www.ifam.fraunhofer.de/de/Presse/Wasserstoffantriebe_fuer_E-Scooter_und_Co.html - use Google Chrome to translate). One important note is that this is a Magnesium Hydride Hydolysis Reaction with half the hydrogen coming from water. The semi-solid POWERPASTE contains magnesium hydride and non noble metal salts as well as a non-toxic ester, there is more detail in this Whitepaper: https://www.zess.fraunhofer.de/content/dam/ikts/zess/documents/POWERPASTE_WHITE_PAPER_2019.pdf). What I would like to see is no new Infrastructure. Something like Professor Kondo-Francois Aguey-Zinsou Hydrogen battery which also uses a metal salt catalyzed Magnesium Hydride H2 storage (read about it here:https://lavo.com.au). Now just use a reversible fuel cell to reduce costs.
Current EV business models are doomed unless manufacturers that have bet their futures on them, such as General Motors and VW, invest in or coordinate on a robust supercharger network. The Electrify America EV supercharger network, which was started by Volkswagen as part of its settlement with the US over the Dieselgate scandal, plans to deploy one of the most extensive electric car charging networks in the US. Lucid Motors and Electrify America are partnering to give owners of the upcoming Air EV three years of complimentary charging. Did UC Davis and Dartmouth forget to consider this?
As GCC points out: Earlier in January, Guoxuan High-tech launched its new-generation LFP cell, with an energy density of 210Wh/kg—a similar level to NCM523 battery cells. At the pack level, module-less pack designs, including CATL’s Cell to Pack and BYD’s Blade Battery, have allowed more LFP cells to be placed into the pack than previous technologies. Yes, LFP batteries do have cost parity with PbA batteries, but they are more than capable of starter motor or lawn mower batteries. However, there are some problems if you do not upgrade thermal management software as Tesla found out in the "Made in China" Model 3 Standard Range plus (SR +) with a battery made with the CATL LFP cells. (Read:"Tesla Model 3 with LFP Battery Has a Cold and Range Problem", at TorqueNews (https://www.torquenews.com/1/tesla-model-3-lfp-battery-has-cold-problem). There could be a fix for CATL or SVolt LFP Prismatic batteries if they use the Penn State battery design (read the GCC post "Penn State develops thermally modulated LFP battery; fast-charging, inexpensive, long-life for mass-market EVs", GCC 1/19/2021). Tesla would need to use a different approach with the 4680 battery, probably using it's excellent thermal management properties (from the patent 20200144676A1, Heat transfer through the base of the cell, and especially heat transfer from the negative electrode, are thereby improved in the disclosed embodiment due to the increased area over which the transfer takes place. The improved heat generation and transfer properties facilitate thermal management of the electrochemical cell.).
What about a Reversible SOFC for long range trucking (<250kW)? What about using Ammonia as the hydrogen carrier ( check" Direct Ammonia SOFC"-https://nh3fuelassociation.org/wp-content/uploads/2012/05/ammoniasammesn.pdf) Now to make it safer by using "solid Ammonia storage" (https://nh3fuelassociation.org/wp-content/uploads/2012/05/amminex_2008.pdf). What do you think?
Three Points about the Penn State system: #1: Self Heating only uses 2% of the battery's total energy and completes this process in 40 seconds (reference:https://ecpowergroup.com/acb/). Note: if your Tesla has the new "Octovalve Heat Pump", you can gain 5% efficiency. #2:Reduced Battery Degradation: Read the Car and Driver Article, Our Tesla Model 3 Has Lost 7 Percent of Battery Capacity in 24,000 Miles, where they state - "We're not too surprised that we're doing worse than average, as fast charging at Tesla's Superchargers is not great for maximizing the battery's life, and we've gotten fully a third of the energy our car has used that way. Supercharging also costs about twice as much per kilowatt-hour of energy than charging at home." #3: This is an All Climate Battery that retains energy at low temperatures.
From Tesla Battery DayPresentation and InsideEVS, Check this out: https://insideevs.com/news/446245/tesla-slide-25000-car-lfp-batteries/.
The heating step is at the cell level using nickel strips and is fast, around 30 seconds based on this article. Asymmetric Temperature Modulation for Extreme Fast Charging of Lithium-Ion Batteries, "we introduce a heated-charge protocol that adds a heating step to warm up the cell from ambient temperature (Tamb) to a high temperature (TH) prior to the conventional constant-current constant-voltage (CCCV) charging (Figure 1B)." (Ref: https://www.sciencedirect.com/science/article/pii/S2542435119304817). Also, the Penn State team is working with EC Power Group (www.ecpowergroup.com). Professor Wang is also the Chief Technology Officer and founder of the startup EC Power. This makes LFP batteries look like the best low cost EV approach, particularly since Tesla also will come out a $25K LFP auto.
The ATR 72-600 jointly manufactured by Airbus and Leonardo is still in production and few modifications would be necessary. Probably just wing extensions like Boeing did on the 777X. What is interesting is that this concept shows a straightforward path to using Fuel Cell electric power. The PW127 used in the ATR72-600 is 27% efficient at Max cruise (https://en.wikipedia.org/wiki/Brake-specific_fuel_consumption) and burns about 735 kg per hour (https://www.fliegerfaust.com/atr-72-sells-better-q400-2469153415.html). So an FC should burn about half that amount with each pod weighing less than1000 kg (Note: the ATR72 carries 5,000 kg of fuel). Liquid H2 is too expensive for commercial aviation (even for space travel). However, H2 storage with the volumetric density of LH2 might solve the problem. Either "Blue" or "Green" Ammonia or the advanced solid state H2 storage being developed in Australia might work better. The real potential for this concept would be in eVTOL. Look at the ASX Modi-One for example, which is a 4 engine tilt wing VTOL. The "Pod" concept could work well for this design.
The hydrogen-fuel-cell-powered “pod” configuration looks like a system that could work in the near term. Probably, based on the ATR 72-600 turboprop aircraft (instead of two PW127 engines @ 2,475 hp each, six 825 hp electric motors, and six 450 kW fuel cells - 78% cruise power). Liquid H2 stored in "slipper tanks similar to the Lockheed JetStar wing mounted fuel tanks. So this could definitely work. Though Liquid H2 fuel costs and infrastructure are another challenge for practical air travel.
@Roger, Please forget about Liquid H2 for General Aviation. This technology has been explored for years and the infrastructure and cost issues are very large. Soviet Russia developed a Liquid H2 commercial aircraft in the 1960's (the Tupolev TU-155) even this was too expensive. NASA solved the technical issues of liquid H2 decades ago (read: https://www.nasa.gov/topics/technology/hydrogen/hydrogen_fuel_of_choice.html. However, even for Space travel, SpaceX and BlueOrigin are using LNG,i.e. LH2 is still too expensive. This is my take on all of this. There is still hope for FC powered aircraft (particularly VTOL). The best bet is solid state H2 storage which has better volumetric and gravimetric energy density than even LH2. Some are looking at Kubas Maganese Hydride, but this is still in the early stages of development. My bet and that includes Sandy Munro is the "nano solid state tech" from Australia being developed by University of NSW professor Kondo-Francois Aguey-Zinsou. You can read about it here: https://www.smh.com.au/environment/climate-change/alchemy-of-energy-breakthrough-offers-mass-hydrogen-storage-options-20200702-p558dj.html. Professor Aguey-Zinsou said the H2 alloy contained titanium and "other common materials", maybe it is based on this research: "Stabilization of Nanosized Borohydrides for Hydrogen Storage: Suppressing the Melting with TiCl3Doping" (reference: https://pubs.acs.org/doi/abs/10.1021/acsaem.7b00082). Maybe this will develop soon.