Electric Vehicles etc

link1896

Is not a gynaecologist but will look at your fork
Indeed the current electricity distribution grid cannot support mass EV charging when we insist a 4 door, 5 seat car that consumes 125-200 watt hours per km is what we actually need to transition to on mass.

If we limit charging power to 2.2kW per household for our Tesla, that’s ~12km of car range per hour of battery changing.


8 hours charge gets us 96km of range, for one car per household. 8 x 2.2 = 17.6kWh.

I know how the energy market will solve this if we give them the opportunity. Load control at the residential DB with the retailers running rolling auctions for the nightly rate for the customer to commit to. Want 11kw for 8 hours (88kwh) at $0.75 per kWh. Let’s say energy costs go bat shit crazy. $0.75 a kWh in metro melb/Syd/Bris.


I’ve been involved with cinema energy efficiency studies where calculated power usage gets real tricky as per the docklands example. Supply authorities tell the consultant “max supply current is xxxx, if you want more it’s xxxxxx and xxx years before we can upgrade”. Pretty funny when someone signs a commercial lease agreement for 10 years THEN finds out their maximum available power is 60% of expected. Distribution capacity issues are costly at a micro level. Nation wide? Can’t see it being resolved. Partially with a hybrid approach? Sure. Yes.



These basic car charging numbers show how tricky the numbers get if we go like for like with electrochemically powered transport replacements for the existing fleet . That’s not an option for all of the people from a grid capacity pov. Residential PV and energy storage demands are going to be insane to meet demand.



A pedal assist ebike MTB uses 10-15 watt hours of energy per kilometre. Remember our car was 125-200 watt hours per km. How many cars on the road have one occupant?

My electronic mountain bike uses about 13 watt hours per km on river side flat single track.
1000 watt hour battery
Gives us a 66km range on single track dirt on flat ground if we use 15 watts per km. Take it up to 20 watts per km so we are at a convenient 1/10th the energy consumption of the car.

We don’t have active liquid cooling on our bicycles lithium ion cells like these fancy Tesla’s do so we are going to charge our bicycle battery cells at 0.5 times rated cell capacity like Samsung and Panasonic tell us we should. We don’t like the red dragon within when we ignore them.

0.5kw for two hours to charge. 1kWh


.

$0.75 to charge our ebike for a 66km round trip.


Cars are not the sole answer. Pedal assist gets the owner moving, and uses a considerably smaller amount of energy.
 

link1896

Is not a gynaecologist but will look at your fork
Thanks… for the slow charge is it 240v or bumped up? As in, going into the car.
230v ac goes it to the cars charger, that’s built into the car.

The pretty Tesla “charger” that’s stands on the concrete at the new shopping centre, it’s nothing more then a decorative cable reel with fancy connectors and energy metering. All the fun electronics are inside the car.

The 230v ac is full wave bridge rectified to 331v dc. The Tesla model 3 uses a 350v dc bus voltage. The 331v charger voltage has to be stepped up to 350v, a boost circuit does this.

Gets really fancy when it’s a 3 please charger.
 

Haakon

Call me Ken, whoreken
Energy has to come from somewhere. I’m not saying we need more generators, however those generators will need to produce more energy.


Sent from my iPhone using Tapatalk
Doesn’t quite work like that. Look up curtailment.
 

mark22

Likes Dirt
Silly thing is charging stations are not universal, you would want to stick with a compatible car for the charger you get installed if you were to change vehicles.
Crazy situation really.
 

Lazmo

Old and hopeless
230v ac goes it to the cars charger, that’s built into the car.

The pretty Tesla “charger” that’s stands on the concrete at the new shopping centre, it’s nothing more then a decorative cable reel with fancy connectors and energy metering. All the fun electronics are inside the car.

The 230v ac is full wave bridge rectified to 331v dc. The Tesla model 3 uses a 350v dc bus voltage. The 331v charger voltage has to be stepped up to 350v, a boost circuit does this.

Gets really fancy when it’s a 3 please charger.
So for the fast charging stations, is it 415v 3 phase going into the car? And it’s onboard electronics does the DC conversion and correct voltage boosting?
 

Oddjob

Can hench anywhere any time
No one freaked out about everyone having a clothes dryer and air conditioning. Neither of which tend to be run in the wee hours when your car is charging on off peak rates.
They did actually. Remember that big jump in network costs 10 years ago?

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link1896

Is not a gynaecologist but will look at your fork
So for the fast charging stations, is it 415v 3 phase going into the car? And it’s onboard electronics does the DC conversion and correct voltage boosting?
Yep for fast charging you need a crap load of power, 11kw looks like the maximum a Tesla will charge at currently. Once into a 3 phase setup, your full wave bridge rectifiers are connected between phases, so 415 x sqrt(2) = approx 586 vdc and it’s a buck circuit to drop back to the batteries system bus voltages.


Yes, on board electronics and management systems are controlling the process. Many many lines of code running on many microprocessors.
 
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