Peter wrote:
To end the internal combustion engine era, all we need is
You don’t have to end anything, the horse carriage era wasn’t ended the day Carl Benz presented his ICE carriage. This will happen gradually so your concern about the grid and power plants isn’t one that I share.
Peter wrote:
batteries with 10x greater capacity
We see great advances in battery technology, still using the same 20 year old lithium chemistry while very promising new chemistries are on the horizon. I got one of the first BMW i3s and after 3 years I got one of the first facelifts. In the course of only 3 years, they have managed to increase the battery capacity by an amazing 50% without requiring more space. Those increases will continue and aviation will get the dividend as well.
The German magazine Pilot & Flugzeug had a very interesting article about the feasibility of an all electric transport category aircraft and they were able to demonstrate that it is feasible. Airbus are investing in that area and it’s clear that it’s going to come.
Peter wrote:
To end the internal combustion engine era, all we need isbatteries with 10x greater capacity
10x beefed up distribution grid
10x more electricity generation
nuclear fusion
Batteries with 5x the capacity at this stage. However, ignoring that I think it’ll be a long time before aviation is off liquid fuels. Ground based transport, particularly personal sized ground based transport, a lot less.
The grid probably doesn’t have to change that much. Right now at night there is massive overcapacity. Charge favourable power rates at night to encourage most of the charging to go on then while people are asleep, and you’ll make the power companies and grid much happier since instead of having massive demand in the day which the grid has to be sized to take, and massive overcapacity at night with machines and power transmission as huge capital costs that are sitting idle and not making money for anyone, the demand is much more consistent over a 24h period. Similarly, you don’t need 10x the electricity generation because now instead of having all that stuff sitting idle at night, it’s now working 24h. The gap between day and night demand is also getting ever larger as the things we power at night become more efficient.
The move to electric isn’t going to be sudden, either – it’ll take decades (despite what some overly optimistic people are saying, like no ICE cars will be getting sold in 8 years time), leaving time for the grid to adapt.
Boeing is reportedly furthering studies on a hybrid 737, with a 3rd electrically-driven fan in the tail-cone, the early results were a lot better than anyone expected.
Hangars should all have their roofs face south and be covered with panels. This is easily mandated even locally.
While full electric may take a while, hybridization could come a lot faster.
Batteries with 5x the capacity at this stage
Currently we are at about 50:1 (battery weight versus liquid fuel weight, for same energy) so even allowing for efficiency gains you need to do a lot better than 5:1 to make it viable except for unusual applications (very short endurance, etc).
I agree with the point about night-time grid utilisation, but this is applicable only once electric cars gets enough endurance to be chargeable primarily at night. This is the case for a portion of the application sphere but that’s it. However it doesn’t get around the more basic point about where the electricity will come from… you have to “burn” “something” to make it: coal, oil, gas, uranium….
The other points are all good (e.g. lower prop rpm is much more easily achievable with an electric motor) but do remember the ~40% overall efficiency ceiling of a steam cycle power station (which includes nuclear ones) so if one takes an overall look at the whole process……
Peter wrote:
electric cars gets enough endurance to be chargeable primarily at night.
That’s the way it works in practice for those with night meters. The one big thing that changes in driving an electric car is that the fuel station is at home, is always open, and takes almost no time to use. So you just plug it in. Or you use plugless charging
So every morning your car is fully charged, and unless you need the full range in a single trip, battery capacity is simply not an issue.
The energy mix is changing, and while at the moment the eco-credentials of electricity aren’t that great, it will improve.
I still believe that aviation is the least viable application of this, because weight matters, cost matters a lot less, and cruise power is a high %age of max power. So in aviation a hybrid is more likely than an outright electrical aircraft, where some combustion engine creates enough energy to sustain cruise, with battery augmenting take-off and climb.
Does the “battery weight to liquid fuel weight” equation take into account the 30% efficiency of a liquid fuel powered engine?
With regards to “steam cycle power stations” it would perhaps be interesting to note that wind / solar projects are now awarded free of subsidies in Europe, and LCOE parity between legacy & renewable generation is expected for 2018. In the US LCOE parity between “steam cycle” and utility scale solar / wind has already been reached.
Even the UK has managed to reach its first “coal-free” generation day (coming down from 23% of generation to 9% in 2016 to lower in 2017) so… it’s definitely possible.
180 kts behind an electric motor.
https://cleantechnica.com/2017/04/05/electric-plane-using-siemens-motor-sets-2-new-speed-records/
Peter wrote:
you have to “burn” “something” to make it: coal, oil, gas, uranium….
What is burned in these examples?
Why this negative tone? Why judge an evolving technology by its past or current state and just assume unrelated givens like coal power generation to make it look bad?
Electric propulsion is coming and us GA promoters should be at the forefront of it because one important justification for the existance of GA (read: state support for its infrastructure) is a testbed for future technologies and training of future aviation personnel. If you stick to your “Lycoming burning 100LL is the past, present and future” mantra, you (not targeting specific people) just contribute to GA’s death.
The fact that my hobby involves burning leaded fuel is something that worries me.
achimha wrote:
Why this negative tone? Why judge an evolving technology by its past or current state and just assume unrelated givens like coal power generation to make it look bad?
Some people just don’t like electric vehicles on a personal basis. It doesn’t fit into their vision of reality or something, I don’t know. They usually set up a smoke screen of nonsense. Here, a smart guy has made a 50 points of what to say and do, to try to slow down the electric car revolution. 
I don’t think getting into the usual “moderator bashing mode” (favoured by a few here) is very productive. If you want a mod who doesn’t post (which I know is the real issue in this case, because I’ve been told so) we can always create one of these
and ask everyone who reads EuroGA to put in say €100 (or ask everyone who posts to put in say €1000 ) and then we can employ some weirdo who knows nothing about flying and just sits there, chucking out people he doesn’t like (like happens elsewhere).
