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The Lilium Jet has 2000 hp and is not really a "jet"(it has 36 ducted electric fans -24 in the wing, 12 in the canard @55 hp or 42 kW each). Also, during cruise it only needs 200 hp. According to CEO Daniel Wiegand, “Today’s batteries are between 260 [and] 280 Watt-hours per kilogram. That’s what you can buy off the shelf at the moment, and these batteries are in the prototype at the moment,” Wiegand said. “With these batteries, the maximum we think we can achieve is something around 300 km range… but that doesn’t mean you can fly it in service,” reference: "Lilium Goes Its Own Way", eVTOL News (Jan/Feb 2020 Vertiflite Magazine. The Lilium Jet looks a lot like the Aurora Flight Sciences XV-24A Lightning Strike, which had 24 electric motors and never made it past prototype stage. The Lilium is also a lot better looking than the Lightning Strike, maybe because it was designed by Frank Stephenson (he is a famous auto designer of Ferraris and McLarens). We will have to see how this interesting design proceeds particularly when it gets higher energy density batteries.
That's right. The 12 small propellers generate lift over the entire wing and since the wing is much smaller it has less drag. Also, after takeoff the propellers will fold back. (Reference: X-57 Home:https://www.nasa.gov/specials/X57/small-wing-act-bigger.html)
The most efficient turbo-compound was the Napier Nomad and it was a diesel. Even this brilliant engine was never considered by aircraft manufacturers because jet engine aircraft like the Boeing 707 would replace all prop aircraft. Jet engines were very inefficient and were soon replaced by turbofans. Todays high bypass turbofans produce over 80% of their thrust from the fan not the exhaust. The Pratt & Whitney geared turbofan with a bypass ratio of 12.5:1 is more like a ducted turboprop, so even more thrust is produced by the fan.
if you are interested in a very detailed look into the use of Ammonia for power generation check out this open source document; "Ammonia for power", Progress in Energy and Combustion Science, Volume 69, November 2018, Pages 63-102. Access at https://www.sciencedirect.com/science/article/pii/S0360128517302320?via%3Dihub or http://orca.cf.ac.uk/115540/1/180910%20JPECS%20Ammonia.pdf.
We need to watch how this develops. This anode appears to eliminate the many problems with lithium metal anodes and has already demonstrated over 1,000 cycles with high volumetric energy density (the battery cell also uses a solid electrolyte and a lithium metal anode with the silver-carbon composite layer). In the same issue of Nature Energy there was an article "Ultrahigh power and energy density in partially ordered lithium-ion cathode materials" by Gerbrand Ceder of UC Berkeley that achieved 1100 Wh/kg using an inexpensive manganese oxide cathode (no cobalt or nickel). Can we combine this cathode with the Samsung anode? Maybe we are closer to low cost, solid state batteries.
LFP batteries look like they will increase in growth thanks to Tesla and also 24M with their semi-solid binder free electrodes. Global Power Synergy PLC (GPSC) is building grid scale LFP batteries and 24M delivered cells last year to GPSC. If you add Silicon Anodes like Enevate is building and 350 Wh/kg looks reasonable. The real value is cost probably below $80/kWh and of course zero Cobalt.
@electric-car-insider, Agree that there appears to be too many rotors on all of these Air Taxi Concepts. MOBi One went from 4 props to 8 contra-rotating props. Bell went the right direction going from 6 ducted rotors to 4 in the Nexus 4x (now looks a lot like the Bell X-22). Canadair in the 1960s went from 4 props on their CL-62 Tilt Wings to 2 on the CL-84 which worked very well. Even though the older tilt-wing tilt-rotor concepts had problems with mechanical driveshafts, too many electric motors will be too complex as well. Simpler appears to be the best approach.
So who has not dreamed of owning "George Jetson's Flying Car"? There is even an autonomous air transport company called "Elroy Air" (George Jetson'e son). The LTV XC142 was a great airplane and should have been produced. It did have problems with the cross-linked driveshaft which is not required on electric aircraft. Another tilt wing aircraft the Canadiar CL84 Dynavert was also very successful. So the tech definitely works. Uber is promoting Air Taxis so they could be in our future (so is Hyundai and Toyota also). Of course, today Air Taxis are called helicopters and a few familiar helicopter companies like Bell, Airbus, Karem, and Piasecki all have eVTOL aircraft designs. Spirit Aerospace knows a lot about about aircraft and composite manufacturing, they are a spinoff of Boeing ( I worked there 10 years ago at a plant that built B-52s). ASX looks good as well, so I hope they have good luck on the MOBi One.
That is a good question @mahonj, According to Urban Transport Magazine, "Retrofitting instead of new-built: conversion from diesel to electric buses" Depending on the condition of the vehicle and the extent of the work, the conversion can cost between 300,000 and 350,000 Euro per bus. This is about half of the cost of new electric buses. Ref:https://www.urban-transport-magazine.com/en/retrofitting-instead-of-new-built-conversion-from-diesel-to-electric-buses/
Even if this Hollywood Pickup never materializes, it is a good marketing strategy. People do buy $100K Pickups/SUV and Southern California does have quite a lot of H2 stations. It would be a great strategy for Toyota, too. Build a Toyota Tundra FCEV or better yet the iconic Toyota Land Cruiser FCEV. Toyota could even use off the shelf components like the AC motors from the Lexus 500h AWD with 177 hp, 221 lb-ft, and a combined output, 354hp. Use the RAV4 Prime PHEV battery to give over 30 miles of EV range. . . . . BTW Davemart, Nikola still plans to use Powercell fuel cell, just made by Bosch who partners with Powercell.
This is truly a "dreamer" project and as @mahonj points out maybe there are some real applications for this novel use of wind, solar, and hydrogen. The first approach would be to use some of these concepts in Hybrid System for Ships already pursued by marine propulsion companies like Rolls-Royce. There is even a large (>12,000 MT) sailing ship Sailing Yacht A that uses an MTU Integrated Propulsion System and sails. For commercial shipping hybrids would work using some of the CMA CGM LNG/biofuel ideas. Of course, there could also be a "nuclear" approach. Small reactors are already used by the military and France is a leader in Naval Reactor design. They just need to be cost effective if they could ever be used in a commercial environment. My current interest is in "Micro Reactors", e.g. the Weastinghouse eVinci, which though small (up to 5 MW) might work in a hybrid propulsion system. This may not be far fetched. Already, the TechnicAtome together with CEA and EDF (with support from their Naval Group) and Westinghouse are looking into SMR design.
Probably should have checked this earlier on their website:"The hydrogen chain step 1: The Energy Observer watermaker" ref:https://www.energy-observer.org/actu/en/the-hydrogen-chain-step-1-the-energy-observer-watermaker/. The Energy Observer is equipped with a reverse-osmosis desalination system with several levels. When two volumes of water – one salty and the other not – are put together, natural movement is created: the fresh water is attracted to the salty water. On the Energy Observer, this process instantly consumes 250 W to produce 90 litres of drinking water, 30 of which are then treated again to be used by the electrolyser. 1 L of fresh water produces 100 g of H2 which becomes water again when the fuel cells make the conversion into electricity.
All good points and the Energy Observer does offer a very interesting use of an H2 fuel cell. First, H2 should be available for the entire cruise since it is regenerated by wind and solar power. Also, it will have potable water as output of the fuel cell which like distilled water used in seaside communities and cruise ships must go through a mineralization process, e.g. KOW Watertreatment.
Last year I checked into if/when Honda would build a Passport PHEV (they had been testing a Pilot PHEV). A Honda rep who had worked at the Honda Alabama plant said told me about the battery weight and said that it would be too heavy for the Pilot/Passport. So I have waited for Honda to build a lighter battery. However, now Toyota is building the RAV4 Prime PHEV. So a tough decision.
Anyone who bought a 2018 Honda Clarity made an outstanding purchase. It will last and still be worthwhile in 20 years. The only criticism is to Honda that hesitates to implement this technology across their product line (caveat I have bought Honda automobiles for over 40 years). The current Honda Clarity PHEV battery is built like a battleship, it is water cooled and will probably last 20 years, if not the replacement cost is less than $5000. Correction: last year in a 02/06/19 GCC post "Honda Partners with CATL on Li- ion EV Batteries . . ." I stated that the Blue Energy EHW5 battery cell was used in the Honda Clarity, it was used in the Honda Clarity FCV not the PHEV. The PHEV uses a Panasonic 27.3 Ah battery cell. You can read all the battery details in the XTECH article "Honda Reduces Engine Displacement for New PHEV(3)" at https://tech.nikkeibp.co.jp/dm/atclen/news_en/15mk/071302227/.
The Honda Clarity is a great automobile. It has only one problem. The 17 kWh battery pack weighs too much (6-800 pounds). This makes the Clarity weigh over 4000 pounds. The battery should weigh 220 lbs (100 kg ). This is what Obrist Powertrain proposes for it's battery - 98 kg, that is 203 Wh/kg and it has 110kW continuous discharge power using standard 18650 batteries (Note: the Clarity 181 hp motor is 135 kW, so higher power batteries needed). Why can't Honda do the same and put their excellent powertrain in all of their models?
This is probably one area where FCEV make sense. Even Nikola Motors, a major proponent of FC Class 8 trucks thinks that with their new battery tech that BEV trucks will handle a large percentage of freight hauling (both Class 7 and 8).
About 15 years ago the US thought it was running out of Natural Gas,and Oil companies burned off much of it as a nuisance. Then Fracking revolutionized the discovery of Natural Gas and now it is the number one fuel source for electric generation. Here are two more articles on Natural Hydrogen: "On Generating a Geological Model for Hydrogen Gas in the Southern Taoudenni Megabasin" (http://www.searchanddiscovery.com/pdfz/documents/2017/42041jerzykiewicz/ndx_jerzykiewicz.pdf.html)and this one "Hydrogen self-diffusion in single crystal olivine and electrical conductivity of the Earth’s mantle" (https://www.nature.com/articles/s41598-017-05113-6).
Over a year ago I read about Natural Hydrogen, mostly related to Charles Joseph Odendhal, Natural Hydrogen Energy Ltd. He had worked for Shell Oil and knew that Oil companies always avoided Hydrogen due to problems with drilling equipment. You can read about it here (https://www.greeleytribune.com/news/energy-pipeline-greeley-man-spends-life-chasing-the-dream-of-hydrogen-drilling/). Also, a technical article that he referenced on ResearchGate,"Evidence for natural molecular hydrogen seepage associated with Carolina bays" (https://progearthplanetsci.springeropen.com/articles/10.1186/s40645-015-0062-5).
Thanks E-P, My interest was related to aviation fuels which need to be liquid. Ammonia will work for Marine fuel like MAN Energy, et al are working on. The Ammonia based liquids work well for rockets (much safer than Hydrazine), just curious if they would be feasible as jet fuel.
After checking into the Joby S4 which has actually flown. This looks like a real contender for eVTOL air taxi applications. Joby Aviation worked with NASA on the X-57 so they know electric aircraft technology and now have major support. The Joby S4 will be an all electric eVTOL with a 200 mph cruise speed and 150 mile range certainly adequate for air taxi requirements. Also, it will be 100 times quieter than a helicopter. In the future companies like Rolls Royce could provide long range capability (they have already successfully tested the hybrid-electric version of the M250 gas turbine in a ground demonstration setting using three operating modes: series hybrid, parallel hybrid and turbo-electric). The M250 is already used in many helicopters and general aviation aircraft.
E-P, What is your take on Nitroalcohols as alternative liquid fuels? Ammonia is even mentioned in the Hydrogen Council as a possible Marine fuel. What about a blend? Ammonia dissolves in Methanol and there is even LMP-103S Rocket fuel that is a blend of ammonium dinitramide, ammonia, and methanol. Of course, economics is the real issue. Just wondering.
ntegrating best practices from the Toyota Production System will help facilitate the efficient mass production of these aircraft . . . According to the Joby website Toyota will share expertise in manufacturing, quality, and cost controls. The Toyota Production System, which I studied extensively was the pioneer in manufacturing transformation and was copied worldwide. While the first applications will be for short range Air Taxis, for longer range cruise rmissions a hybrid approach (more likely gas turbines) will be needed where Toyota has significant expertise. Also, the FAA will probably require an APU even in Air Taxi applications. Several manufacturers like Safran and Honeywell already have small APU that would easily fit this requirement.
So this is "optimized for high volume commercialization and manufacturing at gigafactory scale" and there are other near term battery developments. This is Pure silicon-dominant anode technology tunable with 10-60µm thickness , what about using the thicker (450µm) binder free electrodes that 24-M/Kyocera are producing, and this is with conventional cathode materials, e.g. NCM,etc. What is then needed is to move away from expensive materials like Nickel and Cobalt and look at Conversion Cathodes like the Halide cathodes that Chunsheng Wang/UMD or Young-hye Na of IBM, or the Iron Flouride Cathodes that Gleb Yushin of Georgia Tech are developing. Solid State and Lithium Metal-Sulfur are still in the future, these all look like close to commercial level.
"Xtrac will supply the e-axle to Austrian company Kreisel, which the FIA has selected as the supplier for the phased introduction of a battery-powered propulsion system into this major race series" Also, Kreisel will be the sole supplier of the electrifying kit, developing 500 kW (680hp), this includes a 52.65kWh battery with an innovative cooling system, two 250kW motors (for each axle) and two inverters. The current 2019 rules allow 380 hp and a 1190 kg vehicle weight. So this should be a significant boost in power. For comparison purposes, the VW ID.R which set the record at Nurburgring and Pike's Peak also had a similar setup (2 e-motors, 1 per axle, and 500 kW). It weighed less than 1100 kg, so these WRC cars will be just a little slower. It would be great to see VW, i.e. Audi return. Citroen is dropping out of WRC, but since the Peugeot Group is now combined with FCA, maybe Lancia will reappear (my favorite WRC car of all).