Is it really? Care to elaborate?
"Just stop oil"
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Soldato
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why not? less to go wrong than in a jet.
also chances are it will be hybrid at least for anything that goes beyond the uk ... battery to take off, more conventional engine in the air (hydrogen perhaps) then recharge the battery when descending to land.
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Soldato
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there are already short hop small electric passenger prop planes. as I said earlier tho Imo hybrid will come 1st . many advantages with that. they will be far quieter than conventional on take off and landing but mainly because the energy currently wasted when landing a plane could be reclaimed.
Large batteries have a much greater risk of catching fire though. Maybe battery technology will improve in future, but right now I think it's quite reasonable to be a bit sceptical about the safety of having large batteries powering planes?
There are loads of pictures of electric cars that have pretty much spontaneously caught fire due to battery faults. The fires often seem to be uncontrollable even when the fire brigade get there too. Or even look at the dreamliner which had problems with some relatively small batteries catching fire.
Can just imagine a huge battery fire melting a wing off in minutes mid-air.
Compare that to modern jet fuel powered planes where the risk of fire is pretty minimal, and there are options for extinguishing things like engine fires that seem moderately effective.
Not saying it will never happen or that technology won't improve, but the risk seems significantly higher at the moment imo...
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Hydrogen in planes is never going to happen. It doesn’t contain enough energy for its mass to even factor into the conversation.
Can we please kill off the notion that hydrogen is the answer for everything because it just isn’t.
There isn’t going to be any electric or even hybrid wide body jets anytime soon either.
The best thing the aviation industry can do right now is focus on efficiency, and fortunately that is exactly what they are doing. Efficiency also sells planes, fuel is basically the only relevant operating cost, who ever has the lowest fuel consumption drives the entire market. A more efficient plane will be easier to decarbonise when the technology allows it to.
They have jets now that are basically the size of a 747 but only have two engines rather than 4. That is a great achievement.
Electric planes is not an issue on safety grounds either, can we please kill that notion too. Please state your source that they have a larger risk of catching fire as you seem to suggest you know what you are talking about.
Back in the real world there are not any electric planes in service outside a few light aircraft so it’s not actually possible to tell if one is more risky than the other because there is basically no data. Last time I checked, regular combustion planes also catch fire and they do so more often than you think.
The issue in aviation is purely down to the energy to weight ratio and we are miles away at the moment from anything other than kerosene. The only viable alternative even in the table at the moment is synthetic fuel derived from plant matter but the cost makes it unsustainable at the moment.
As for electric cars catching fire, you know a combustion cars catch fire spontaneously all the time right? Per vehicle, ICE cars catch fire more than electric ones. It literally happened to my wife’s friend a few months ago, they went from driving down the dual carriageway to a burnt out shell in under 5 minutes. Two infants in the car as well, terrifying experience.
Can we please kill off the notion that hydrogen is the answer for everything because it just isn’t.
There isn’t going to be any electric or even hybrid wide body jets anytime soon either.
The best thing the aviation industry can do right now is focus on efficiency, and fortunately that is exactly what they are doing. Efficiency also sells planes, fuel is basically the only relevant operating cost, who ever has the lowest fuel consumption drives the entire market. A more efficient plane will be easier to decarbonise when the technology allows it to.
They have jets now that are basically the size of a 747 but only have two engines rather than 4. That is a great achievement.
Electric planes is not an issue on safety grounds either, can we please kill that notion too. Please state your source that they have a larger risk of catching fire as you seem to suggest you know what you are talking about.
Back in the real world there are not any electric planes in service outside a few light aircraft so it’s not actually possible to tell if one is more risky than the other because there is basically no data. Last time I checked, regular combustion planes also catch fire and they do so more often than you think.
The issue in aviation is purely down to the energy to weight ratio and we are miles away at the moment from anything other than kerosene. The only viable alternative even in the table at the moment is synthetic fuel derived from plant matter but the cost makes it unsustainable at the moment.
As for electric cars catching fire, you know a combustion cars catch fire spontaneously all the time right? Per vehicle, ICE cars catch fire more than electric ones. It literally happened to my wife’s friend a few months ago, they went from driving down the dual carriageway to a burnt out shell in under 5 minutes. Two infants in the car as well, terrifying experience.
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Caporegime
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Small prop to jet engine is a massive task for electricity. They are not even comparable. A 747 uses 150,000 litres of fuel in 10 hours of flight. You wouldn't even get off the ground with batteries needed for that. It would weight more than the titanic and be about the same size too.
Permabanned
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I would have thought it would be the other way around? The power of the jet turbine for take off and in reserve for aborting a bad landing, and the lesser energy demands whilst at altitude in flight served by electric means.
The weight and volume of batteries is bad enough in wheeled vehicles, in a commercial aircraft built to carry as many passengers or as much freight as possible they'd be abhorrent to a designer.
Caporegime
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So basically in a nutshell flying will become increasingly expensive because the oil companies will not be subsidising it with the sale of petrol and diesel.
small ‘Cessna’ style planes are a lot easier because they typically only need to be in the air for an hour.
It’s not the taking off or the landing that is the issue, it’s just there isn’t enough energy in the battery to undertake any commercial flights.
Possibly, possibly not.
Other users will start buying up the cleaner fuels. For example shipping uses basically anything they can get at the lowest price. So at the moment that’s bunker fuel because you can’t burn it anywhere else other than out at sea because it’s horrific so it’s very cheap. They’ll happy take diesel that burns much more cleanly and they have to use it already when coming into port anyway. As road demand drops, they’ll happily pick that up at the right price.
All modern ships are electrically propelled anyway so if it makes sense for them to swap out some heavy fuel generators for petroleum based ones, I’m sure they will do so very quickly. In fact I’m pretty sure that is the short-med term plan as demand from other uses drops and there is excesses of other fuels in the market.
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Airbus have small electric planes and are investing in hydrogen as well.
www.airbus.com
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Now if hydrogen can become viable then that will push hydrogen cars along faster.
Electric flight
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Hydrogen
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Now if hydrogen can become viable then that will push hydrogen cars along faster.
Soldato
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Fail to see how batteries can ever match the mass to energy density of fossil fuels unless they can make the batteries a structural part of the plane. The energy density of fossil fuels is fantastic and as you use them you lose the weight.
the hydrogen is deployed via a fuel cell to create electricity with intermediate battery (for power boost) ... and as you say hydrogen has a higher energy density than batteries - to wit. the range of toyota Mirai.
Fuel required oxygen to combust, so unless you wing had split open a very rare issue, aka Concorde, it's a very safe energy storage system. Ie ignore 99% of films with exploding cars and planes.
Batteries on the other hand have everything built in to expel all their energy in a matter of seconds or minutes. If such a plane had a runaway battery failure, it could turn the plane and it's passengers into a molten fireball. At least you'd die fast I guess.
The energy density of batteries at peak performance is under a 1/4 of jet fuel, and their isn't any weight lost during the flight so you need more energy to complete the same journey, not less. So 5-6 times the weight for your energy storage.
If we could make a battery in the future that could match the energy density of aviation fuel, the volatility of the battery would be insanely high, like flying with primed bombs attached to your plane.
You car isn't a commercial jet plane, so don't compare the two. Maintenance of commercial jets is highly regulated.
Any fire related stats between ICE and electric cars are going to be very poor at the moment because there are so few electric cars and they are a lot newer.
The biggest problem with electric cars will be when they are involved in a major crash, that battery will be more dangerous than fuel, when electric cars become common this will be a big issue.
Battery fires are very hard to put out as they don't require additional oxygen, so can burn for hours. Imagine this in a major RTA?
But not as dangerous as hydrogen if that ignites.
You do know there are fire suppressants designed to smother an ev battery fire?
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Smothering a short circuit would just temporarily delay the inevitable. It's not a solution to an EV battery fire.
I've not mentioned hydrogen, so not sure why your telling my this (and assuming I don't know).
EV fire suppressants are poor, you need to do some more research if that's meant to be a positive?
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