Charging My 2016 Leaf With Solar

[brucevan]

I love my 2016 Leaf and use both Levels I and II grid charging at home.

I am thinking of getting an 8-panel off-grid solar system with charge controller for two (or more) 200AH Deep Cycle batteries and a 1,000 watt (or 2,000 watt) Off-Grid Pure-Sine Wave Battery inverter.

I would like to, at least occasionally, partially charge my Leaf with Level I charging from the inverter in the above-described solar system.

I would appreciate it if any who are knowledgeable on charging a Leaf with solar could comment. Thanks!

[Tsiah]

I don't have any first hand experience with it, but it is possible to set up an OpenEVSE to charge only when solar is available.
I'm still learning the tricks to the commands through the WiFi in the OpenEVSE.

There's also a combination EVSE/solar inverter manufactured by SolarEdge.

You're not going to charge very quickly at 1-2kWh. 1.1kWh is all you get out of the stock EVSE 120V@12A.

[GerryAZ]

The stock Nissan 120-volt EVSE allows the car to draw 12 amperes so you will need an inverter rated at least 1500 watts continuous (2000 watts would be better to provide some reserve and avoid running the electronics at 100% current). You will also need to have the neutral of the inverter grounded for the EVSE to allow charging (most inverters and portable generators have neutral floating instead of solidly grounded so a temporary grounding jumper is needed). There are several threads regarding charging from portable generators that explain this issue.

[brucevan]

Thanks Tsiah and GerryAZ.

This is what I'm going to try: Renogy 500 Watt 12 Volt Solar Premium Kit (includes 40 amp Charge Controller), 2 X Renogy Deep Cycle AGM Batteries 12 Volt 100Ah, and a Renogy 2000W 12V Off-Grid Pure-Sine Wave Battery Inverter w/ Cables.

I will be sure the inverter neutral is grounded.

In theory, this should work. I'll post here how it works out. I know Level I is slow of course. Not sure how long it will take AGM batteries to discharge. Should get this set up in about 2 weeks. I'm in Florida so lots of sun even this time of year.

[GerryAZ]

You should be able to charge for an hour (maybe a little longer) if you start with fully-charged 12-volt deep cycle batteries. Let us know how well it works.

[BrockWI]

I have done this with two 12v 100 amp batteries and a xantrex 2000w true sine wave inverter. It runs about 40-45 minutes before going in to low voltage alarm drawing about 125 amps. The batteries aren't dead but with such a large load the voltage just sag's to much. You will need at least 300 amps at 12v if you want to run the stock EVSE for an hour and for the sake of the batteries I would recommend at least 400 amps to run an hour.

[brucevan]

From the comments it looks like the maximum time I will get charging my Leaf with the stock EVSE from two 100AH AGM deep-cycle batteries will be about an hour (if that).

My original calculations were: Two fully charged 100AH batteries can deliver 50% of their capacity -- 100AH. Now, if the stock EVSE draws 1,440 watts (12A X 120V) wouldn't I get about 8 hours before depletion (100AH/12Amps = 8 hours).

If the EVSE is the only draw -- 1,440W on the 2,000W inverter -- it is well below the inverter capacity. Maybe the problem lies with the batteries not being able to handle a strong continuous draw. If so would a larger battery bank help?

What am I missing here? All comments welcome.

[magico13]

You're forgetting about voltage. AHr is only half of the equation when looking at energy storage, you really need to think about kwh, which is more useful here.

Let's say you can pull half of the energy out of the batteries safely, so 50AHrs each at 12 V gives you 1200 watt-hours or 1.2 killowatt-hours. Your EVSE draws 1.2 amps at 120 volts, for 1.44 killowatts. If you want to figure out how much time you'll get before you run empty, just take the total energy and divide it by the rate of usage, so 1.2 kwh / 1.44 kw = 0.83 hours, or about 50 minutes.

Your LEAF battery is probably around 75 Ahr or so but has WAY more energy stored than your little 100AHr batteries because the voltage is 30 times higher. Compare 75Ahr x 360V = 27kwh to the 1.2kwh present in your batteries. It's pretty clear you'll need substantially more storage and generation to charge your car for more than a tiny bit using solar.

Your original calculation can be useful, but remember that you'll put 12 amps out of the inverter, but going into the inverter you're going to have to pull 1440 watts out of the batteries, or 120 amps. Again it's clear your 100Ahr of batteries won't last long with 120 amps coming off them. 100Ahr / 120 amps = 0.83 hours = 50 minutes.

[brucevan]

Thanks magico13, that explains a lot. I'm still learning this electric stuff

[SageBrush]

Bruce,
Why are you keeping the panels off-grid ?