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We're Charging Our Cars Wrong

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Re: We're Charging Our Cars Wrong

#141

Post by somerandomqaguy »

TechDebtDevin wrote: post #41
ForOldHack wrote: post #19

Earlier quoted context omitted.

Like Henry Ford tried on the Model T: The Model T was offered in three fuels: Gasoline, Electric, and Alcohol. It only took I think less than a year to make it Gasoline only.

Is there any universe where we go the electric route instead of gasoline back then? I imagine the range was nothing

Probably not.

The gas piston engine didn't just power cars, it also powered aircraft, armoured vehicles, and trucks. Anyone using electric vehicles by the time World War 2 broke out against a gas piston enemy would've been constantly outmanoeuvred and outgunned. And the logistics chains to bring men and materials to the front of the enemy's front lines would've been far faster then any electric trucks at the time. Especially without the modern day micro controllers that make modern battery management systems possible.

Re: We're Charging Our Cars Wrong

#142

Post by robertlagrant »

IneffablePigeon wrote: post #120
monero-xmr wrote: post #118

Earlier quoted context omitted.

Where I live the electricity is primarily generated by fossil fuels. The light is weak for many months of the year, and wind power is apparently way too expensive if they remove the subsidies (weird!). Wouldn’t gas cars just eliminate the middleman of fossil fuels -> power plant -> car? Like we did before EVs? I would love nuclear power but it doesn’t appear to be happening

EVs emit less carbon even when powered by a fossil fuel dominated grid. The power plant is more efficient than your car, and often uses LNG rather than petrol or diesel, and there are still some renewables in almost any grid. In addition, air pollution close to where you live will be lower. In addition, the grid can be decarbonised over time and your car will become greener as it does.

While a power plant is more efficient than my car, transmission reduces that efficiency sigificantly (I think here in the UK transmission accounts for 40%-50% of usage, although I may be misremembering).

Does that affect the calculation at all?

EDIT: I was totally wrong - it's more like 7%. Still interested whether that affects the calculation, although it's much less likely to!

Re: We're Charging Our Cars Wrong

#143

Post by mschuster91 »

brabel wrote: post #112
cyberax wrote: post #64

Earlier quoted context omitted.

Imagine a catastrophic fault: a dude in another car drives into your car, and a conductor in the car breaks off and energizes the car body. The current now goes through the car body into the ground, and also through the grounding wire back to the charger (EVSE). It's a phase-to-ground short. The charger tries to interrupt the flow, but the short circuit fries the power electrics in the buck converter (MOSFET/IGBTs ca…

Imagine a catastrophic fault: a dude in another car drives into your car at the petrol pump. The petrol pump starts dropping huge amounts of petrol on the ground. Part of the car wreck falls back on the ground and ignites a fire, causing the whole station to blow up, killing everyone within 100 meters. Clearly, we cannot allow petrol stations to exist.

Modern petrol pumps have break-away detection, it can recognize when the nozzle/hose is broken along the chain - I _think_ it works via the nozzle being lower gauge, which means when the flow rate suddenly increases there must be a high volume leak in the hose. And even then, it's only a few liters a minute. That's enough for a nasty fire, yes, but you can usually extinguish it with a handheld extinguisher.

Cars, at least modern cars, are also built with safety systems in mind. The fuel line from inlet to tank isn't open as it used to be, nowadays there's a spring actuated flap that is pushed aside by the nozzle (as well as vapor suction systems in the nozzle) so vapors cannot escape and form an explosive atmosphere.

On top of _that_, all parts from nozzle over hose to pump to tanks have safety features to prevent a catastrophic explosion: flame arrestors and inertization, and buried tanks.

So, we didn't ban petrol stations, but in the interest of safety and environmental protections (reduction/near elimination of VOC escape) we mandated changes in how cars and petrol stations are made so that even the dumbest possible user (aka, someone smoking a cigarette right next to his Ferrari getting refilled with 102 octane fuel) will more likely than not either not explode at all or the explosion will be relatively harmless in scope.

Re: We're Charging Our Cars Wrong

#144

Post by stahtops »

ralph84 wrote: post #111
stahtops wrote: post #81

This doesn't solve fundamental problems with how America has built its charging infrastructure. We never should have placed hardwired cables on the L2 or L3 chargers. The CCS plugs are broken about 50% of the time? It's a joke. Rented an EV in Europe... the cable is in the trunk! You own it. Take it out, plug it into the charger, plug it into your car. Having a bad day? Drive over the plug? Smash it with a hammer? Do…

Many DCFC chargers these days have liquid-cooled cables. Not sure how that’d work with a portable cable.

Fair point. There are benefits to having the cable on the charger for sure, I’ve just found L3 chargers to be unreliable (and when they don’t work it’s always a massive hassle - no one is going to the L3 with 50% SOC)

Maybe the CCS plug is just not up to the reps they get, hopefully NACS will be better.

Re: We're Charging Our Cars Wrong

#145

Post by Dylan16807 »

raldi wrote: post #91

Buried deep in the article, what the clickbait headline alludes to: Car chargers are too complicated and expensive. We can make them simpler and cheaper while keeping them safe, which would let us build many more charging stations.

What do you mean buried? The article says that at the end of the introduction section.

And it's pretty reasonable to explain how current chargers exist before suggesting the alternative. There are nicely labeled sections to help with skipping forward.

Re: We're Charging Our Cars Wrong

#146

Post by jfim »

monero-xmr wrote: post #127
MostlyStable wrote: post #123

Earlier quoted context omitted.

I guess it depends on your driving habits and homecharging situation, but after a year with my EV, I wouldn't go back if God came down and personally told me that every EV resulted in a baby seal being clubbed. Among the many advantages, never having to go to a gas station is so much better.

Why is going to a gas station difficult? I’m far more concerned about needing to charge in a pinch than needing to find a gas station

If you can charge at home overnight, then your "tank" is full every morning. The logistics are a bit more complicated for long distance road trips though.

Re: We're Charging Our Cars Wrong

#147

Post by Dylan16807 »

robertlagrant wrote: post #142
IneffablePigeon wrote: post #120

Earlier quoted context omitted.

EVs emit less carbon even when powered by a fossil fuel dominated grid. The power plant is more efficient than your car, and often uses LNG rather than petrol or diesel, and there are still some renewables in almost any grid. In addition, air pollution close to where you live will be lower. In addition, the grid can be decarbonised over time and your car will become greener as it does.

While a power plant is more efficient than my car, transmission reduces that efficiency sigificantly (I think here in the UK transmission accounts for 40%-50% of usage, although I may be misremembering). Does that affect the calculation at all? EDIT: I was totally wrong - it's more like 7%. Still interested whether that affects the calculation, although it's much less likely to!

Wikipedia says 7.7% distribution loss.

Re: We're Charging Our Cars Wrong

#148

Post by robertlagrant »

Dylan16807 wrote: post #147
robertlagrant wrote: post #142

Earlier quoted context omitted.

While a power plant is more efficient than my car, transmission reduces that efficiency sigificantly (I think here in the UK transmission accounts for 40%-50% of usage, although I may be misremembering). Does that affect the calculation at all? EDIT: I was totally wrong - it's more like 7%. Still interested whether that affects the calculation, although it's much less likely to!

Wikipedia says 7.7% distribution loss.

That is a lot lower than I remember! I'll try and find my source for that.

EDIT: I can't find that source, and I found a load of sources around 7%. Thanks for the correction.

Re: We're Charging Our Cars Wrong

#149

Post by LunaSea »

jdminhbg wrote: post #37
jauntywundrkind wrote: post #36

Earlier quoted context omitted.

The timeline is even longer (and with such good cause). It also took till March 2023 to specify federal requirements for a charger! That's not a bad thing, it's not unreasonable at all. We didn't have any open systems for charging until then! There were no federal standards for what to build or how to stay or fall out of compliance! Before you start paying people to build chargers, you have to have some direction for…

Ok, but taking two years to come up with a big document of standards while Tesla was able to just do all that by themselves and then build more chargers for less is kind of the issue. I appreciate that it's not easy, but the not-easiness is the problem.

Didn't Elon fire the supercharger team anyways?

Re: We're Charging Our Cars Wrong

#150

Post by tomas789 »

I'm no electrical engineer but would that really be so much cheaper? A buck converted is essentially the same thing where the transformer is replaced by an inductor. You get rid of a bit of copper but all the power electronics to do the high-frequency switching is still there. Together with most of the components.

They "estimate" this would save 60% on galvanic link, and on the rest, you can save another half. So that would mean you are at 20% cost plus some ground wire fault detection HW.

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