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mahonj
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@GGOGM, The vehicle weighs 175 kg, but you have to put a person in it so I added 75kg for one adult male hence 250 kg. This will increase the rolling resistance, but not the aerodynamic resistance, which is the main drag once you speed up. The "patented internal gear hub" will increase the gearing, but it don't overcome wind resistance, so it won't go much faster. If you think this will increase the speed from 30kph to 70kph you are deluded. Please furnish examples of the etrikes with a 1 kw motor that can go 70kph. Use the ebike simulator to figure out its capability, but expand the frontal area to 1m^2 and reduce the CD from 0.9 to 0.7 or 0.5. If you consider this as a 30kph etrike with a range of 50 km, you won't be so disappointed. It still has merit.
Cool, they can do incredible things with wood, nowadays. Here are some wooden skyscrapers, for instance. https://www.theguardian.com/cities/2019/jul/22/canadian-cities-take-wooden-skyscrapers-to-new-heights#:~:text=Wooden%20skyscrapers%20are%20made%20of,when%20it%20comes%20to%20earthquakes.
Hmmm. 1Kw, 1kWh - OK. If you put the parameters into an ebike simulator, you can get a range of 49 km with a 22Ah, 48V battery and a speed of 30 kph. (Weight 250 Kg, frontal area 1m^2, cd 0.7) http://www.electricbikesimulator.com/ I don't see how you can get to 70 kph with a 1 kW engine. The solar panel looks tiny, so you won't get much out of that. Looks like typical indigogo "optimism" with little respect for the laws of physics. There is a lot to be said for very low power, low speed vehicles, but let's stick to reality.
If only De Havilland had known this when they designed and made the Comet Mk 1 in 1949-52.
If they can make aluminium parts lighter and safer, all the good. I wonder when we'll see this in a product ?
Why not use batteries for E buses. You can predict the range and work out the charging schedule. Using H2 looks like green flag waving. If they just wanted to reduce pollution and CO2, battery buses would have been just as good and probably cheaper.
Scooters are lethal because they have small wheels and you stand almost directly over the first one, and they go quite fast. Thus, if you hit something, or break moderately hard , you go straight over. In a bike you site between two large wheels, well back from the front one, so it is inherently safer, unless you cycle straight into something. Scooters are a lot of fun, and look cool and are easy to pack away, hence their popularity, but they are still lethal. If you wear a helmet and gloves (ideally with a leather face), you'll be safer (but less cool). No simple answer. As to where to put them - on the road. They have wheels (and aren't wheelchairs). On the road, with the bikes.
This begs the question - what is the best thing to do with hydrogen? [ Assuming we will have considerable excess renewable electricity ] Should we: Use here making steel? Use it in fuel cells in cars? Use it in IC engines in cars (or buses) Use it in fuel cells in aircraft ? or in some other chemical process. Here are some comments of mine: H2 is difficult to store and transport and there are loses making it. thus, Use batteries if you can, much lower loses than making H2: (so no to cars and buses) Batteries are too heavy for aircraft - may be a possibility here. Could also work for ships (or maybe just use methane, which is clean other than the CO2 (!)). The ideal one would be a chemical process that can work with or without H2, so you make it on demand when there is excess renewable electricity.
OK, you would probably want 100-200 kW of a generator for a bus - the 30-40 was for a car.
@william, I agree, but you could just use a gasoline or diesel generator that can generate 30-40kW in as neat a package as possible. You can keep the rev band and power band narrow and this should simplify the engine. This is what the nissan e-power system does. Only add a 10-20 kWh battery so many days, you don't need to run the engine at all, just plug it in every night.
Very good indeed. Sensible to focus on speed and braking only, which is way simpler than steering and emergency braking. And it actually saves money on fuel and maintenance. The same ideas could be used for EVs too, I imagine, where they really need the range. If I were a driver, I would be wary, however. Once they get the speed sorted, they'll start working on steering. This will be easy enough on dry, straightish roads. In a perfect world, the driver would be able to have a snooze. (Maybe by placing a dummy in the cab so as not to alarm people too much). This would work quite well. The driver brings the truck to the highway, gets going and has a snooze. Then, an hour or so before the destination, he (or she) gets up, has a stretch and takes over. However, the engineers and accountants keep working away, and one day, a few years later, the truck does the whole journey by itself. Maybe the driver is in an office (or at home) and uses 5G to pilot the vehicle to and from the highway.
It looks like a bait and switch to me. They talk abut bioLNG, but also about liquifying gas from the grid. It is certainly better to use LNG in ships than bunker oil, but hardly carbon neutral, even if you sweeten it with some bioLng. Here's a question: would you be better off generating H2 from unused renewables and using it to crack long chain hydrocarbons and get the H2 into the fuel system in that way, or keeping it as "pure" green H2 (which is hard to store and transport) ?
Liquid fuel that can be made from biomass and can be used to generate H2 for a fuel cell. What's not to like ? Any figures on kW / kg and kW / L. I assume it is too soon to talk about cost except in hand wavy terms.
@Roger, OK, but it sounds like a waste to use H2 in gas boilers. Better to keep it for fuel cells. Maybe you could make large bore low pressure H2 pipes to move it around (or maybe I am talking through my hat).
I imagine it is more economical to have fewer, larger, hydrolizers than one at every gas/petrol station. Once "they" set their mind to it, they'll probably find an economical way to transport it / pipe it around. Maybe they could line normal steel pipes with a stainless steel coating.
One thing they could do would be to make the roads lighter in colour, which should reflect more light and keep them cooler. On the other hand, this would reduce image contrast between the white lines and road surface, which is not something you want for ADAS systems and auto drive systems. Never simple.
" the International Energy Agency recognizes that CO2 removal is expected to play a “key role” in the energy transition" I don't see that. IMO, the energy transition is about generating energy without CO2, not about taking CO2 out of the air. This is a different thing - both are good and useful, but they are different and independent (IMO). It always strikes me as easier to not put the CO2 into the atmosphere in the first place, rather than taking it out afterwards. (The only exception I can think of is aviation). If you put the same amount of effort into closing and substituting Coal plants and burning forests, you would get much more bang for your buck. Surface transport can be electrified, as can most sea transport (eventually). Air transport is much harder as batteries and hydrogen tanks are bulky and heavy for long / medium range.
it is a good idea. Set a price and let suppliers compete and users get some certainty.
@lad, I'd say they will keep working on H2 storage for aircraft and get enough in that. Or else use Methanol or ammonia for a different cycle. (I wouldn't like to be around if an ammonia plane goes down, though). Remember, it doesn't have to be electric, it just has t produce no or very little greenhouse gases and be afforable and safe. Here's a great book on zeppelins if you are interested: "Dr. Eckener's Dream Machine"
Power increases with the cube of the speed if aerodynamic drag is the major factor (as it is in fast cars and planes). So the trick for E aviation is to go a bit (quite a bit) slower than current planes. The advantage of short range aviation is that you can hop over things like cities and estuaries etc. They may still learn a bit from the engine design and the other bits - if you can fly at 1/2 the speed, you might get 4 times further (probably not 8 times because you'll need to keep enough lift to make the plane fly!). In general, I am skeptical about electric aviation for anything over 500 miles as batteries are too heavy and H2 storage is heavy and bulky, and H2 is a difficult fuel to store and transport (and usually comes from methane). Maybe just use the most efficient aircraft you can and spend the money on offsets (i.e. actually build stuff, not just buy slips of paper on an exchange somewhere). E land vehicles are easy enough, E ships can use heavy batteries or large H2 tanks, but making this stuff light enough to fly is a problem.
"with the ability to charge up to 3.5kW" ? Do they can that they can charge EVs at 3.5kW, or they can charge the batteries in the charger at 3.5 kW? Assuming they can on ly charge the batteries at 3.5 kW and get say 7 hours of sunlight / day, that only allows them to charge ~24 kWh per day. If that is the case, it is a bit weak. You'd be better off with say 10kW charging and 3x the battery capacity. Or better still, a grid connection to charge the battery as well as the Solar PV.
Reminds me of my dad's books about the 1929 Schneider trophy S.6b aircraft and similar. https://en.wikipedia.org/wiki/Supermarine_S.6B https://www.pinterest.co.uk/pin/472948398344284862/?nic_v2=1a5ks6eQB (Not in looks, just in outlook)
Good stuff. Methanol could be a useful synthetic fuel using CO2 from whatever source. Much easier to store and transport than H2 + you can use an ICE to use it. A methanol hybrid could be a very low co2 car with no range problems. (But you'd have to distribute the methanol).
A bigger battery would help, and so would wireless charging (as an option), or a solar roof (say 600w x 5 hours = 3Kw = 10 extra miles). You have to charge it every day you drive it for it to be effective. You could give black marks for days when it is used uncharged and nag the driver into charging it. What you want to get to is a plug in with a range extender, rather than today's PHEV. And it has to be as cheap as possible.