Charger capacity needed for departure setting use?

[Ragman]

Converting a parking lot over to Level 2 chargers with plan to retrofit 240v/20 amp circuits on existing 120v/20 amp (wire gauge is sufficient). Expecting this to give 3 kwh (27 kwh in 9 hours) for employees which is more then needed for 99% of employees daily mileage recovery. However question lacking knowledge on is if employee sets departure time for "5:00 pm" is the 3 kwh rate sufficient to provide land power to preheat Lightning cabin/battery in January weather (-20)?

Expected Chargers to be Used: Grizz-E Smart set to 16 Amp

Reason for lower power rating: Minimal existing panel/wiring changes needed by converting existing 120/20 circuits to 240/20 circuits at panel.

We would like to provide "better than 120" charging to employees without incurring excessive capital expenses on electrical upgrades.

Any insight is appreciated.

Sponsored

 

[RickLightning]

Not even close.

 

[chl]

"However question lacking knowledge on is if employee sets departure time for "5:00 pm" is the 3 kwh rate sufficient to provide land power to preheat Lightning cabin/battery in January weather (-20)?"

240V x 16A is 3.84kW rate (kW is a rate in watts, i.e., power, while kWh is a measure of energy, used or stored).

I do not believe 3.84kW is anywhere near enough power from the line (land power) to precondition the Lightning battery and pre-heat the cabin at -20F in a reasonable amount of time based on other posts I have read about real-life results at higher temps.

I saw one person posted using 8kWh in 45 minutes at a temp of 30F.

However...

If your employee plugs in at 9am and unplugs ate 5pm (8 hours later) that is:

8hr x 240V x 16A = 8hr x 3.84kW = 30.72kWh energy added to the Lightning.

A standard range battery holds 98kWh fully charged.

So they would be adding about 1/3 energy capacity to the truck with an SR battery.

So if they use some of that added battery capacity they could pre-condition the battery and pre-heat their cabin using some of that stored energy.

The other question is though: How much capacity do they need to get home?

 

[Ragman]

More is it a hard yes/no on battery preconditioning under "x" kw of charger - ie does it even try? Partial being better then none.

The average roundtrip would be 50 miles which the 30 kw even in Lightning as worst case would meet needs. Trying to fill gap for employees without home charging (apartments etc).

 

[TaxmanHog]

More is it a hard yes/no on battery preconditioning under "x" kw of charger - ie does it even try? Partial being better then none.

The average roundtrip would be 50 miles which the 30 kw even in Lightning as worst case would meet needs. Trying to fill gap for employees without home charging (apartments etc).

At that low amperage, unlikely to see substantial battery warming if at all, the cabin warming will occur though, likely negligible change in SOC while on the plug.

I'd advise the employees to pre-condition (departure time) before heading to work, then when they arrive there is still sufficient heat in the pack to allow your EVSE's to continue to slowly charge the battery. [-20c / -4f ]

Sponsored