Lightning off-grid charging Solar Array Build w/Agrivoltaics

[MurphysLaww]

So, we've really already started testing the Array install, but this thread will track our 3600 watt, 10 panel, off-grid solar array and charging setup. I'm shooting for a 4 year payback, if we drove the average amount of miles. It may not actually be my payback as we both work from home, and don't put a lot of miles on the Lightning.


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We're in central Texas with the associated brutal heat, so this system will also be a small scale Agrivoltaic project, to shade 4 raised bed salad gardens. Likely, once it's going, with some machine learning added in.

The average amount of miles, from research seems to be around 13,800/yr. To get there, we have this basic parts list so far:

• $1400 - 10 x 360 watt panels, used, from SanTan Solar
• $2300 - 4 x 12v 200ah (10kWh)PowerQueen LiFePo4 Batteries from PowerQueen direct, may bump up to 8 batteries.
• $900 - Refurbished EG4 6000EX Low frequency Hybrid Inverter
• $300 - 2 x Eco-Worthy ground mount systems, and concrete footing blocks
• $200 - cabling
• $150 - Actuators for single axis solar tracking - shooting for a 20% increase in output

First test mounting of two panels started, and we'll be working more this weekend. Finally have some weather that isn't trying to kill us. Ignore the Vevor actuators, they are moving to my solar powered tool shed, and are being replaced with slightly higher quality Eco-worthy actuators, pending working out a partnership with Progressive Automations for MUCH higher quality actuators with Hall sensors and positional control.

We are going to try to integrate the Ford Charge Station Pro into this build, charging at, likely, 24amps.

Anyway, this is one of the reasons to go electric, so you can have your own filling station. Eventually, there will be free fuel for the remaining life of the panels, and Batteries. Side benefit is a mini-split cooled garage.

We're keeping this relatively portable, as we believe we're going to pack this system up with the Lightning and ship everything to a central american country to be named later to live out semi-retirement, so this is essentially, a proof of concept.

Some of what I'm doing here is already covered in projects on my youtube channel. Doesn't everyone have one?

https://www.youtube.com/@racingtogreen2023

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[Jseis]

My daily burn rate is 38-48 KWH (90-100 commute miles averaging 2.2-2.5 mi/KWh). Replenished nightly in 4-6 hours. That’s not insignificant battery storage. 3-4 PowerWalls. The Lightning sits outside at work for say 9 hours. At $.0634/KWh, inexpensive power hardly justifies a $30K investment unless it was on the garage (nice steep roof-good southern exposure ). Interesting concept and worth considering in high cost energy areas.

 

[MurphysLaww]

My daily burn rate is 38-48 KWH (90-100 commute miles averaging 2.2-2.5 mi/KWh). Replenished nightly in 4-6 hours. That’s not insignificant battery storage. 3-4 PowerWalls. The Lightning sits outside at work for say 9 hours. At $.0634/KWh, inexpensive power hardly justifies a $30K investment unless it was on the garage (nice steep roof-good southern exposure ). Interesting concept and worth considering in high cost energy areas.

Definitely use case specific. The numbers wouldn't add up for you. As economies of scale come, it will get more reasonable. .06/KWh is stupid cheap, more than 50% lower than the national average and lower than I've heard of, really anywhere. I thought Washington runs like $.11/KWh(All that hydropower, I assume?). Texas power is relatively cheap, and our's runs $.156/KWh. Predictions are that our's won't increase a lot over the next 10 years. For some east coaster's it's going to get even more expensive, but their solar output is lower. The national average, per FRED, has risen from $.135/KWh to $.171 ,but that isn't expected to continue at that rate. One never knows though. All it takes is a joker like Putin to pull something else, and you'd be at the mercy of irrational price shifts once again. Ours changes every time there is an ice storm.

We're shooting for around 15-20kw/day output, but we can plug the car in during the day because we WFH. Obviously, not everyone can do that, and it will allow us to get by with only 10KWH of batteries. I'm expecting to be surprised with losses as well. Already know that the EG4 inverter is going to use around 3.2kWh/day in idle output. We can only put 10kw into batteries. The truck will stay plugged in, and charge at 24amps. At our current burn rate, we'd only have to put around 11 KWh in the truck per day, on average. We calculate somewhere around 1.929KW/Mile.

Racking is in. It's surprisingly solid. We don't get a lot of wind between the house and the fence. We'll see how it does with an additional 500lbs of panels.

Should have the last two actuators to replace the black ones, in another week.

Rest of the garage cabling came in as well. Getting ready to fire up the EG4 6000ex, and see if it works.

 

[Jseis]

Definitely use case specific. The numbers wouldn't add up for you. As economies of scale come, it will get more reasonable. .06/KWh is stupid cheap, more than 50% lower than the national average and lower than I've heard of, really anywhere. I thought Washington runs like $.11/KWh(All that hydropower, I assume?). Texas power is relatively cheap, and our's runs $.156/KWh.

Racking is in. It's surprisingly solid. We don't get a lot of wind between the house and the fence. We'll see how it does with an additional 500lbs of panels.

Should have the last two actuators to replace the black ones, in another week.

Yes, our power rates are stupid low at $.0634/KWh and principally due to a public utility district buying power from Bonneville Power Administration (A federal authority like the Tennessee Valley Authority). Of note, because power type futures (green, hydro, solar, wind, co-gen, nuke, etc. coal, etc) are bought on an exchange and the grid can “ship” the proportional mix anywhere, power users buy in the futures market and very competitively.

I can commute in a Lightning at $2.5-$2.8 $$/day V. $25+ for gas/diesel going the same distance. It makes any investment a real challenge though heat-pumps, better windows, etc are always good choices. EVs are a no brainer yet there are big tired 4x4s blowing though $35-$45 a day in diesel. Solar water heating has a better ROI than solar electric battery storage.

 

[watchdoc]

I'm not a huge fan of the 6000EX but it's not terrible. I prefer the MPP unit. Both have fairly high idle consumption and you need to make sure they will charge the batteries with the inverter OFF. Skip the power queen batteries and get EG4 Server rack batteries as well so you can use communications. This makes things much easier to manage and monitor. The goal would be level 2 charging so you need to see how low the Lightning will charge at 240v. You don't have enough panels to sustain 3600 watts.

Make sure you at least add inline fuses to those panels, a panel disconnect, bus bars, and a DC rated breaker. Don't cut corners or you'll regret it.

We charge our Leaf 90% of the time from a small 3kw solar array and a Growatt inverter.

I've been relatively pleased with the Eco Worthy mounts but for 10 panels, I would probably choose the EG4 mounts.

 

[MurphysLaww]

In some ways, this build is all about cutting corners, but yes, there are inline panel fuses inside the combiner box, and then, the combiner box fuses. I’ve managed to not learn anything the hard, smoke test way, so far, so appropriate fusing will be at battery to inverter, with a PV disconnect as well.

yeah, I said, 24 amps, but, I meant to say 12 amps, which is the lowest setting the charge station pro has a setting to charge at. This is all a POC, for when we expatriate to a possible entirely offgrid location, where We’ll panel up to closer to the max the 6000ex can do, and then we’ll reset to 24 amp charging if it all works.

The Power queens, are just due to knowing them, and having them have performed perfectly for nearly two years in our 1200 watt studio shed, which get’s charged and drained nearly daily. I bought a battery balancer for the two we have, only to find they were perfectly balanced after a year and a half. 10kW in the powerqueens came in at 20% less than pretty much any server rack battery.

 

[MurphysLaww]

More Progress this weekend. Six panels up, four to go.

Rest of the eco-worthy actuators arrived. Still waiting to hear from Progressive Automations on the Hall Sensor IP68 actuators. Depending on how these function, I'd guess I still might switch them out, but after some back and forth, I haven't heard from them, so I'm going to go with these for now. I'm a ways from getting cute with the software anyway.

With a potential for 10Kw in the batteries from the previous day, and a stretch goal of 20k of generation, we could possibly put 30kw into the truck in a day.

There is a cool video by one of the larger channel youtube channel owners(Everyday Dave) that explains some of the financial method behind the madness.



Waiting on a few panel mounts we thought we had and at least one fuse and breaker I thought I had...

It's reasonably solid, but I'd guess not nearly as much as most people would want. We don't get a ton of wind between the house and the trees here, so I think I'm safe for now. Most of the weight of the panels is on the fence and those posts are in concrete footings buried at least 24 inches down.

Evening Orientation

And, with it up in gardening/Morning position

Sharp eyes might note I have 6 panels wired in series. Not how it's designed for. It will be 5 in series paralleled with the other 5. It will be a max of 200ish Volts, and around 20amps to the charge controller.

 

[MurphysLaww]

More progress...

Looks like the linear actuator companies are not interested in partnering, so I'll be attempting to make the ecoworthy 18" actuators work. So, we're just waiting on a few panel to grid mounts to arrive, and deciding on how to run the array to inverter cabling, and setting up the AC breaker box, and running the flex duct to go.

Looks like the refurb EG4 probably works. Saved about $300 to $900 on it depending on where you might be able to pick one up new from.

This guy will be going on the wall soon...

Here, to the left of the Chargepoint:

 

[MurphysLaww]

Moving right along...

Tightened up the racking some.

It looks like we will be working with ProgressiveAutomations, so these actuators will be replaced with 24" Hall sensor models from them soon with full positional control.

Got some garage wiring done, and picked up the duct for the array to charge controller run. Really just waiting on a few panel mounting brackets, mounting the combiner box, picking up some breakers, and drilling the garage entrance hole.

 

[Ford Motor Company]

So, we've really already started testing the Array install, but this thread will track our 3600 watt, 10 panel, off-grid solar array and charging setup. I'm shooting for a 4 year payback, if we drove the average amount of miles. It may not actually be my payback as we both work from home, and don't put a lot of miles on the Lightning.

We're in central Texas with the associated brutal heat, so this system will also be a small scale Agrivoltaic project, to shade 4 raised bed salad gardens. Likely, once it's going, with some machine learning added in.

The average amount of miles, from research seems to be around 13,800/yr. To get there, we have this basic parts list so far:

• $1400 - 10 x 360 watt panels, used, from SanTan Solar
• $2300 - 4 x 12v 200ah (10kWh)PowerQueen LiFePo4 Batteries from PowerQueen direct, may bump up to 8 batteries.
• $900 - Refurbished EG4 6000EX Low frequency Hybrid Inverter
• $300 - 2 x Eco-Worthy ground mount systems, and concrete footing blocks
• $200 - cabling
• $150 - Actuators for single axis solar tracking - shooting for a 20% increase in output

First test mounting of two panels started, and we'll be working more this weekend. Finally have some weather that isn't trying to kill us. Ignore the Vevor actuators, they are moving to my solar powered tool shed, and are being replaced with slightly higher quality Eco-worthy actuators, pending working out a partnership with Progressive Automations for MUCH higher quality actuators with Hall sensors and positional control.

We are going to try to integrate the Ford Charge Station Pro into this build, charging at, likely, 24amps.

Anyway, this is one of the reasons to go electric, so you can have your own filling station. Eventually, there will be free fuel for the remaining life of the panels, and Batteries. Side benefit is a mini-split cooled garage.

We're keeping this relatively portable, as we believe we're going to pack this system up with the Lightning and ship everything to a central american country to be named later to live out semi-retirement, so this is essentially, a proof of concept.

Some of what I'm doing here is already covered in projects on my youtube channel. Doesn't everyone have one?

https://www.youtube.com/@racingtogreen2023

This is amazing! Thanks for sharing

 

[MurphysLaww]

It's looking likely that the "refurbished" EG4 6000ex hybrid inverter is going back to signature solar. There are unbalanced L1/L2 circuits, which is probably why it was RMA'ed previously. Signature Solar, on initial impressions, struggle with operations, and customer service. We'll see how difficult it is to send back. We'll probably replace it with one of the new EG4 6000xp's which seem to be much higher quality, and have a few handy features at a decent price.

That said, we're getting impatient, so we've found an old CMAX charge 120v 12amp charge adapter, and we're installing the panels, running everything into the garage, and will be trickle charging(1440 watts) from the panels running into a leftover 80amp Epever MPPT charge controller feeding a 2000watt Roarbatt inverter. It's what we were originally using to power the off grid art studio, until we swapped out for a victron charge controller, and a roarbatt 4000watt inverter, so we had enough overhead running the mini-split to keep the fans off in the inverter, which start at 1/3 of the inverter capacity. It's cool as this epever is a pretty good value and does up to a 48v system @ 200v and over 4000watts of panels, for under $300. It'll be nice to get some use out of it.

The contract arrived from Progressive automations as well, so we'll be getting a discount on their linear actuators in exchange for covering them in the how-to videos. Some of the more advanced functions of the solar tracking and agrivoltaic sides of the project are contingent on their hall sensor-based positional control.

With the likely changes due to the inverter, and going to the different actuators, it's probably going to increase the total system price from the mid to low $5k range to around $6k.

***edit, ran wires for the first series of panels, and looks like with 4 panels in series, I'm already at 189v, so we'll start getting some eventually free energy from 4 panels, instead of 5 for the moment since the max voltage on the epever is 200.

BTW, is it just me or do the ads really jack with this forum's operation ?

 

[MurphysLaww]

Well, I was able to root out a Ground bond issue with the current inverter, so it looks like we’re moving forward, got the Charge Station Pro running with no ground faults, and it started charging without issue on test. Our first 2.6 kw from the system!

Just waiting on panel fixing mounts now to install the rest of the panels, run the outside 8awg into the conduit and bury it, and we’ll be charging with the sun soon!

Progressive Innovations is waiting on our order for the hall sensor linear actuators and then we’ll be in business on the tracking side…

Then I’ll be building the single axis tracking, and irrigation pump Arduino cloud control box, and we’ll start playing with some basic machine learning (TinyML).

 

[MurphysLaww]

Well, couldn't wait. So hooked up the first series of 5 panels with it appears, no issues.

Currently (pun non-intended) charging the the truck with a mix of solar and battery, which seems to be working. There have been issues with the inverter I'm using and this, so we'll see. I think the one thing I have going for my setup, is that we're charging at such a low rate, but we'll see when the batteries get lower and/or the inverter has more PV to work with. It's cloudy today, and I was getting just under 300watts from the 5 panels.

Setting up SolarAssistant next on a Pi-3 if I can find it and a spare memory chip.

Let the payback begin!!!

last night 12 amps as expected:

Set in FordPass, and in the Charge Station Pro dial potentiometer.

Chargepoint grid connected set to 32 amps, if we need a quicker charge.

Today, tidied up some:

Combiner box with one series:

lil' rainy today... panels in windy storm config.

 

[harry wilson]

Nice content on that channel ! keep it up

Tutuapp 9Apps​

 

[MurphysLaww]

Getting ready to start the videos on this on the channel. Been waiting on the panel mounts, and dodging the having to send the inverter back means I might get started on it this week.

***edit - just after typing the previous, Amazon delivery showed up. Wasn't scheduled until the 22nd, but threw the last three panels on during lunch, and ran the other MC4 jumpers and voila' almost 1kW on a pretty cloudy day.

crap solar day. This 5.4kW
array on the house put's out around 32kW on a full sun day.

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