Electric cars

[wildhorsesracing]

I am seriously considering an electric car, I have plenty of solar panels and wondered what other folks are doing to charge their electric cars from the panels? Is the charging mechanisms DC or AC? Anyone installed a chargeverter just for their electric car yet?

 

[Lt.Dan]

Regular DC to AC inverter, then use an EV charger to go from AC to 300+v DC.

 

[MichaelK]

There are three standard charging levels here in the US, Level 1, Level 2, and Level 3. Their specifications are.....

Level 1: 12A at 120VAC (1440W, or 1.44kW)
Level 2: 10-50A at 240VAC (2400W-12,000W, or 2.4kw-12kw)
Level 3: XA at 480VDC (commercial charging stations only)

Saying you have "plenty of solar panels" is a bit overoptimistic I think. Do you have enough panels to put out 1440W from 7am till 5pm? That would give you about 10 hours of charging, only at level one. That means maybe 2-3 days to fully charge the EV battery.

I myself have 4500W of panels on rotating mounts, and I think I could match level 1 charging from about 7:30 in the morning till about 4:30 in the afternoon. That's only about 13kWh total of power. I might do 10A at 240VAC from maybe 8:30am till 3:30pm, call that 17kWh.

Could the EV owners here please chime in as to what their day to day kWh values are from routine day to day driving.

 

[400bird]

Level 3 charging isn't a thing, it just goes to DC charging. Typically, faster, hence DC Fast Charge.
But, that's not applicable here.

Another option is a level 2 charger that can adjust current and follow solar output.

This day isn't the best example, but you can get more solar into the car than a constant charge rate will allow.

 

[Lt.Dan]

Could the EV owners here please chime in as to what their day to day kWh values are from routine day to day driving.

I keep pretty good track of this, and my average over the last 6 months is 15.4kWh/day.

I do drive more than the national average though

 

[wildhorsesracing]

I have ~14kWh of solar panels installed and another ~14kWh of panels yet to install so I was thinking about building another solar array that we would park electric cars under and hopefully use DC to DC charging during the day.

Has anyone tried this?

 

[400bird]

I have ~14kWh of solar panels installed and another ~14kWh of panels yet to install so I was thinking about building another solar array that we would park electric cars under and hopefully use DC to DC charging during the day.

Has anyone tried this?

Great idea, many have discussed it. But the only hardware available to do this is commercial level ($$$$$)
It's more economical to allow the conversation losses and charge with AC and allow the car's onboard charger to do the work.

 

[Lt.Dan]

Great idea, many have discussed it. But the only hardware available to do this is commercial level ($$$$$)
It's more economical to allow the conversation losses and charge with AC and allow the car's onboard charger to do the work.

Agreed. Any DC to DC equipment you find will be far too expensive.

 

[Hedges]

Another option is a level 2 charger that can adjust current and follow solar output.

This day isn't the best example, but you can get pretty more solar into the car than a constant charge rate will allow.

View attachment 156246

If that is commercially available, either level 2 charger with MPPT input or that somehow is told with communication how much AC is available, that would be the way to go.

For AC coupled systems off-grid (Sunny Island pioneered this, but a number of others also available), the signal is frequency.
Just need to monitor AC frequency. At 60 Hz and below, charge at maximum rate. As frequency increases above 60.0 Hz to 60.5 Hz, ramp charging down to zero.
(Rule 21 frequency-watts GT PV inverters will deliver 100% up to 60.5 Hz, then ramp down to 0% at 61.0 Hz.)

DC coupled PV systems, I don't know what signal is available.

For California NEM-3.0 customers, who get a reduced credit for exports, the signal when on-grid would come from a current transformer. Adjust charge current to reduce export to zero.

 

[Bkord]

I have ~14kWh of solar panels installed and another ~14kWh of panels yet to install so I was thinking about building another solar array that we would park electric cars under and hopefully use DC to DC charging during the day.

Has anyone tried this?

The simplest, cost effective, way to do this is 240 ac.

 

[Murphyslaww]

Jehu Garcia has recent videos on a mobile system.

I'm going to do a standalone, off-grid, split phase, 48v dual system like what Will has here to power a mini-split for my garage, and charge our Ford Lightning.

 

[watchdoc]

I have 3kw of panels, a 3kw Growatt (SPF3000TL LVM-ES), a EG4 LifePower4 battery, and I use a Zencar adjustable EVSE to charge my Leaf+. The Zencar can charge from 8amps up to 16amps @ 120v. I've run nearly a megawatt of solar charging through this system with nary a hiccup. On a sunny summer day I can add 50+ miles to the Leaf.

 

[billvon]

Has anyone tried this?

I only know of one company doing this right now (Enteligent) and they are a ways out from having an affordable commercial solution.

 

[Danke]

I only know of one company doing this right now (Enteligent) and they are a ways out from having an affordable commercial solution.

Yep, they were supposedly working with Sol-Ark. They said that over a year ago, still haven’t seen a retail product for sale:

Enteligent

Our EV Charger is game-changing and will be available in early 2022.

enteligent.com

https://img1.wsimg.com/blobby/go/cee57ca6-01e1-4f12-894e-0a3b5bd6c817/downloads/Enteligent_Solar_DC_EVSE_Data_Sheet_v2.1.pdf?ver=1688132667331

 

[McKravitts]

Regular DC to AC inverter, then use an EV charger to go from AC to 300+v DC.

While this is the simplest and most direct approach, it is not the most efficient for solar.
The typical efficiencies of a solar system charging an EV with a mppt cc, battery bank , inverter, EV cahrger are approximately;
mppt controller 95%
inverter 95%
battery discharge 99%
Onboard EV charger (avg) : 85% *

Net efficiency: 76 %

A loss of 26 % of the collected solar energy seem unnecessary since the goal is to simply charge li batteries.

Most of this loss could be avoided by using an mppt controller designed specifically for the battery bank used by the vehicle.
Does anyone know of an EV that comes with an option for direct solar charging?

*Sadly, the on-board chargers are the ones to blame the most when it comes to energy loss as they are usually between 75 and 95 percent efficient.

 

[Lt.Dan]

My Tesla actually tracks charging efficiency and it averages 94-96% on 240v. My stats are as follows:

PV to SolArk MPPT 98% (conservative)
Invert DC to AC 95% (rated to 96.5%, but conservative)
Car charger: 96%

Total: 89.37% efficient

 

[timselectric]

If you want to go from solar panels to DC EV charging. You are going to have to design and build a custom system for your specific vehicle.
Can it be done? Absolutely.
I may be doing this, myself. But I will be charging a diy EV conversion. So, it's a much simpler endeavor.

 

[billvon]

Most of this loss could be avoided by using an mppt controller designed specifically for the battery bank used by the vehicle.
Does anyone know of an EV that comes with an option for direct solar charging?

Any EV with a DC fast charge option can be direct solar charged with the right equipment. (A CCS adapter and a Solis HV inverter, for example.)

However, the only vehicle I know of that can charge the traction battery directly from solar is the 2023 Prius Prime, which can be fitted with a 190 watt solar roof.

 

[timselectric]

Any EV with a DC fast charge option can be direct solar charged with the right equipment. (A CCS adapter and a Solis HV inverter, for example.)

If you can trick the vehicle into believing that a DC fast charger is connected to its CCS port. (Via communications protocols)

 

[McKravitts]

I found this article online.
Any comments?