climate control on L1 charging?

[adric22]

You know, there is a simple way to answer this question. I could do it, but I'm too lazy.

• Step 1 - Buy a Kill-o-Watt or similar device which reads amps and plug the L1 EVSE into it.
• Step 2 - Plug car into L1 charger
• Step 3 - Measure current draw (should be around 12 amps)
• Step 4 - Allow car to completely finish charging cycle.
• Step 5 - Use iPhone to turn on heater
• Step 6 - Measure current draw

So, if the current draw from just the heater is less than the current draw from charging the battery, then we'll know that the L1 EVSE is not being used to is full capacity.

However, if you think about it most of your little portable heaters you buy at Wal-Mart for $30 run on regular 110 volt household plus and usually pull between 8 and 12 amps. They also produce quite a lot of heat in order to heat up an entire room. In the case of the leaf, it just needs to heat the interior of the car. So I see no reason why it would need to pull more power than that.

Same true of a window-unit air conditioner. They pull around 12 amps also, so again that should be enough power to cool down a car. Plus I'd be willing to bet the A/C in the Leaf is probably a lot more efficient than a $100 window unit air conditioner.

[Mark510]

This test should settle the question. Here is what I did/observed:

On a very cold day (55) I turned on the car while it was plugged in (L1) at about 75% charge. I turned on the climate control in Auto and set it to 77 to simulate a remote control activation request.

The on board energy gauges show about 1.2kW used by the climate control. Plus about 120W for Other Systems. Probably about 1.3KW total. The Miles gauge did not drop so it was probably not pulling anything significant from the batteries.

So if its drawing 12A on 120V it has about 1.44kW to work with. Giving a hundred watts for losses in conversion it looks like it is configured to use only shore power (no batteries) to run the heater when on L1. Of course that doesn't leave anything significant left over for charging the main battery bank.

[JPWhite]

On a very cold day (55) I turned on the car while it was plugged in (L1) at about 75% charge. I turned on the climate control in Auto and set it to 77 to simulate a remote control activation request.

The on board energy gauges show about 1.2kW used by the climate control. Plus about 120W for Other Systems. Probably about 1.3KW total. The Miles gauge did not drop so it was probably not pulling anything significant from the batteries.

.

Glad you consider 55 very cold 43 here this morning.

I noticed something interesting yesterday that tells me the car will use battery power to pre-heat a vehicle even if it is connected to a power source.

Car was charged to 80% overnight on my home L2 Blink EVSE.
6 minutes prior to leaving for work I manually started a pre-heat using carwings. (I left earlier than normal and the timer had not yet kicked in). When I got half way down my driveway I noticed the dash indicated that it would take 10 minutes at 240v to charge the vehicle. Normally that message does not appear until I have driven a mile or more. I used one more bar than normal going to work that day.

I surmised therefore that initially the pre-heat maxes out the heat cycle, probably at close to 6kW, then as the car warms drops down to say 1.5 kW and uses any excess power from the EVSE to top off the battery. Even when connected to an L2 charger it can't deliver the 6kW initial draw given that the charger is rated for 3.3 kW.

On a normal day the pre-heat takes up to 20 minutes prior to my departure, plenty of time to restore the battery to 80% charge during the latter half of the heat cycle if connected to an L2 EVSE.

As for the L1 EVSE, I'm sure that it will suck the battery down initially and will most probably never be able to put it all back by the end of the pre-heat cycle.