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The Electric Vehicle Future: Where is all the power going to come from?
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ogden:

--- Quote from: Someone on February 18, 2020, 09:54:07 pm ---
--- Quote from: ogden on February 18, 2020, 08:20:17 pm ---
--- Quote from: nctnico on February 18, 2020, 07:43:40 pm ---Over here hydrogen costs 10 euro per kg.  Electricity from a public charging point costs 0.47 euro ct per kWh on average from Allego (excluding an hourly tarif if you leave the car parked for too long in some cases). So the Mirai costs 50 euro for a full load of hydrogen and an average EV (480km at 225Wh/km) costs 50.76 euro.

--- End quote ---
Public chargers "over there"? :) It was about charging @home, in US. Whatever. Even using your numbers cost to fully charge Tesla 3 equipped with 50kWh battery (400km range): 50*0.47=23.5 EUR.


--- Quote ---Now tell me; given the better range and shorter fueling times which car would people who can't charge from their own sockets prefer?

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Diesel :-DD

--- End quote ---
Electricity vs hydrocarbon vs hydrogen vs whatever as a fuel source varies wildly from country to country. Same topic 5 years ago:
https://www.eevblog.com/forum/chat/problems-if-we-all-had-tesla-cars/msg705793/#msg705793
Things have changed a little since then but it still rides on the electricity price (everywhere?) having no transport taxation, and the majority of countries taxing fuel at much higher rate. As alternative energy sources for transport start to become significant then there will be changes to the way they are priced/taxed. Distance and/or weight based pricing for vehicle use could be introduced to level that. Radical changes in taxation have occurred before in Australia where the government provided rebates (subsidies) to convert or purchase LPG cars, and then just years later upped the taxes on LPG:
https://www.mynrma.com.au/membership/my-nrma-app/fuel-resources/the-story-behind-the-rise-and-fall-of-lpg
The economics of that fuel source fell apart, and people went back to petrol/diesel.

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Yes, sure. Then there is depreciation and service cost. My point was that hydrogen generation & fuel cell is way more inefficient than battery charge/discharge, that's it. @nctnico proudly tried to convince that what I say is lame, it was debunked long ago, yet as we see he struggle to debunk it even using cherrypicking of data.
tom66:

--- Quote from: GeorgeOfTheJungle on February 18, 2020, 09:45:00 pm ---An EV needs:

-Neodymium magnets.
-Lots of expensive copper.
--- End quote ---

So does a hybrid ICE; and if the coming EU regulations are anything like future US ones, then pretty much every new car will be mild hybrid or full hybrid.  Not all EVs require neodymium magnets, the original Model S for instance is rare-earth magnet free (AC induction motor) as is the Chevy Bolt (if I recall correctly.)  Also, the Model 3 motor contains a large amount of aluminium where technically feasible, to reduce the manufacturing cost.


--- Quote from: GeorgeOfTheJungle on February 18, 2020, 09:45:00 pm ----A heavy and costly electric motor that weights MORE than an ICE
--- End quote ---

Really?  I'd like to see sources on this.  Are you comparing a fully assembled ICE vs an EV motor+drive inverter?  What counts as part of the "ICE" here?  Is this just the block?  The whole car including the battery vs. ICE car? 


--- Quote from: GeorgeOfTheJungle on February 18, 2020, 09:45:00 pm ----A 12V battery just like the ICEs
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Model Y is slated to not have a 12V battery any more [1], and this is the trend in the EV industry.


--- Quote from: GeorgeOfTheJungle on February 18, 2020, 09:45:00 pm ----A 60..100 kWh battery made of thousands of Li-Ion cells
-A complicated BMS
-A charger for the Li-Ion battery
-A cooling/heating system with pumps for the Li-Ion battery
-A cooling system with pumps for the electric motor
-A cooling system with pumps for the power electronics.
-An electric motor driven HVAC with heat pump
-A litany of current, voltage and other sensors for the BMS, inverter, electric motor, and cooling systems.
-and so on

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Finally we get onto some actual parameters that an EV really needs and the key differences between EV and ICE.

But all of these things are electronics that are faily reliable.  Voltage sensor?  You mean a couple of resistors into the ADC pin of an embedded controller?  I think that will survive a million miles :).

You have not got O2 sensors sitting in hot exhaust streams heated to 600C.  You have not got oil pressure and temperature sensors.  You have not got camshaft position sensors, knock sensors, fuel injectors, a multi-shaft gearbox actuation system (if automatic; my auto PHEV-hybrid has 12 actuators in its gearbox), MAF sensors, a throttle body actuator, etc.

For what it's worth, anyone thinking about a hydrogen vehicle as less complex: they're EVs, with 100kW inverters and Li-Ion batteries, just with a hydrogen power plant (fuel cell) on board.  It's always seemed odd to me that you'd carry your power generation with you, because it will always be less efficient to make a small power generation station than a larger one.  Perhaps we should just have a way of storing the energy we need in some kind of "battery"...

[1] https://insideevs.com/news/332478/tesla-model-y-to-ditch-12-volt-battery-95-less-wiring-than-model-3/
nfmax:
And no catalytic converter full of high-value metals conveniently positioned for a chav with a battery powered angle grinder to remove while the car is unattended...
nctnico:

--- Quote from: coppice on February 18, 2020, 10:51:05 pm ---
--- Quote from: mikeselectricstuff on February 18, 2020, 10:45:18 pm ---
--- Quote from: GeorgeOfTheJungle on February 18, 2020, 09:45:00 pm ----Delicate hi power electronics for the inverter (hundreds of kiloWatts !)

--- End quote ---
Delicate ?
Are we seeing significant failures of electronics over the last few years of production EVs ? Nope.

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This is one of the things I find quite impressive about electric power in vehicles to date, whether its full EVs or hybrids. There is a substantial amount of high power, high stress, electronics built to minimum cost in all of them, but you hardly ever hear serious complaints about the reliability of this part of the system.

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Maybe that is because most of the EVs are positioned in a higher segment. At some point there will be quality cuts by some brands to compete on price.

Also I do recall quite a few Teslas have issues with their electronics which affect the useability of the car.
tom66:
I think the reliability of the Prius drivetrain should be evidence that EVs will have no significant reliability issues.  Priuses can easily do a quarter-million miles with just regular maintenance, and this is with their original hybrid battery pack. A battery pack that is cycled every couple of miles and sustains charge/discharge of >30kW (for a 1.5kWh capacity that's pretty aggressive.)

Obviously some brands will be worse than others, and quality control issues will still exist.  Tesla is an interesting case because they had a lot of early reliability issues with the Model S but now have a smaller warranty claim rate than almost any other US manufacturer (https://www.warrantyweek.com/archive/ww20190718.html) even though they seem to prepare for the worst by setting aside more per car.

I wouldn't, however, buy an older Model S out of warranty: it is a huge collection of new and experimental technology with only Tesla able to repair it.  I'd wait until more independent garages are competent enough to repair EV drivetrains.  As others have stated, the drivetrains may be reliable, but the cost of a failure is large.  It is probably as expensive to repair an inverter (to manufacturer standards) as it is to rebuild an engine.  But as EVs become more mainstream this will be less of an issue.
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