Lightning off-grid charging Solar Array Build w/Agrivoltaics

[MurphysLaww]

...and first sunny day since we got the EG4 up and running. Without the panels even oriented to the morning position, we were already above idle consumption at 7:30am. At 10:00am we were up over 1kW. Should be a good sign for production. I think we can say we are well on our way to removing our EV from affecting our rickety grid.

When the S/O comes back from Home Depot, I'll hook up the charge station pro and see if we have any issues with the solar/battery priority with significant Solar coming in, but not enough to produce 12amps at 240v.

Solar Assistant was a welcome easy install on the old Raspberry pi 3b I've had lying around forever. It needed a use. Took a couple usb cables to find one that the EG4 liked.

I'll eventually start utilizing the MQTT broker.

These settings are going to be particularly helpful and are more straightforward in SA.

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[MurphysLaww]

...and charger plugged in. Draw on Load and Batt as one would expect. Dropped the measured Battery voltage by 20% which could be a problem with low voltage settings. Such is life with LiFePo4 batts. Unplugged the truck, and it went back up to 70%. If you had EG4 server rack batteries with BMS with communication, perhaps this wouldn't be an issue or as much of one.

It looks like the Charge Station Pro has around 5-8 watts of idle usage.

 

[Hammick]

Super nice array! However, if there is any possibility of wind gusts or tornados I'd be looking for ways to reinforce things or put a wind break fence around it. Recently installed a 4.3kw ground mount at our Montana place and the Iron Ridge engineers required schedule 80 pipe at least four feet in the ground with concrete.

Even with such a robust ground array I'm still worried about losing our panels at some point. Two years ago our area had major damage from sustained category 4 winds. Our weather station's last transmission before breaking was 123.7 mph

 

[MurphysLaww]

Super nice array! However, if there is any possibility of wind gusts or tornados I'd be looking for ways to reinforce things or put a wind break fence around it. Recently installed a 4.3kw ground mount at our Montana place and the Iron Ridge engineers required schedule 80 pipe at least four feet in the ground with concrete.

Even with such a robust ground array I'm still worried about losing our panels at some point. Two years ago our area had major damage from sustained category 4 winds. Our weather station's last transmission before breaking was 123.7 mph

Definitely, worry a little bit about this, but this is less than 40 feet from the house, so the house and the trees behind are a good bit of wind break. We don't tend to get much wind back there.
Horizontal orientation or evening, tilted towards the house, away from the fence, will likely be the storm orientation. We know we may add footing blocks and struts on the other side of the fence as reinforcement. There are metal posts on the opposite side of the fence, with concrete footings, but I imagine, that will cost less than $100, but we are trying to keep costs down.

 

[MurphysLaww]

And first real day of production winding down. The Tracking (manually dropped) now has allowed the 10 panels on the fence to pass up the output of the south facing house 16 panel array. It happened around 3pm. It'll be interesting to see how long it keeps producing.

We're using 18" linear actuators now, but will be swapping to 24" so, we'll be experimenting with a bit more angle both ways, morning and evening. We've added 15 miles range to the Lightning, of the 30 mile daily goal we have for this system, in only 2.5 hours, so it's looking good so far.

 

[invertedspear]

I've been loving following your updates. Please keep it up.

 

[MurphysLaww]

didn't hit "reply" last night.

And, all done for the day. Down to 100 watts at around 5pm.

Moved the panels back to morning orientation, so we'll get a full day tomorrow. Tomorrow appears to be a full sun day. Should be interesting. I'll start moving the panels around noon.

Still working on a deal with Arduino for an evaluation gigawifi board to hopefully run both the tracking actuators, and the smart garden irrigation from one board. If not, I have an IOT REV2 carrier, with a 1010 wifi board for the smart garden and an UNO R4 for the tracking. I still need to hit amazon for some higher amp motor driver boards.

 

[MurphysLaww]

So, oriented the panels to morning config for the morning, and we're producing 30% more than we were at the same time yesterday (9:30) with the panels oriented flat(horizontal).

We were at about 840 watts, and today, we're at 1215 watts today. That is best case, so that's good. By this weekend, I should have the auto-tracking implemented.

 

[MurphysLaww]

I've been loving following your updates. Please keep it up.

Mainly, I've been wanting to show that even with some interesting features, this is not hard to implement. You have to have $5k-7k-ish to invest, a little space, but literally, in 3-4 years, anyone can have free fuel. How much, and how fast you want charging to happen is limited by the Hybrid inverter you choose, and the size of your battery string. This is a higher return investment than just about any, dependent on your electrical costs.

almost all sun charging!

 

[roadhouse]

Just wanted to post and say that I've been following for a while, awesome to see your progress! Love the updates.

 

[MurphysLaww]

Just wanted to post and say that I've been following for a while, awesome to see your progress! Love the updates.

Thanks. I wasn't entirely sure it would work with my configuration as others have had issues with this particular hybrid inverter, the EG4 6000ex, and It's a refurb. So far, with a hiccup or two, it's working.

Would it work at a higher amp draw ? I'm not sure. Running at 12amps may be the only reason it's working for me. The inverter would likely struggle running at 24 amps, as it's close to it's max output(at 240v), but I may try 16. I don't have enough solar to run it at 16amps either, but it'd likely feed it from the batts until they drain.

 

[MurphysLaww]

Moved the panels to horizontal at around 12:30pm and lost 100 watts, down from 2.2kw to 2.1kw. Today, there must be some sort of haze, while full sun is also suffering from the winter overall angle, even the house, which I use as my control, is running at about 85% of it's max.

Yesterday, a bit earlier, we hit 2.6kw for a bit, but seem to be maxing out around 2.2kw today.

The house is normally at 4.5kw at it's max.

 

[DarkL1ghtn1ng]

Just found this thread and while I could never do this, this is very cool and I am enjoying reading along!

 

[MurphysLaww]

Snafu...

The powerqueens LiFePO4 BMS shuts down quick somewhere around 11.75v per battery it appears. This caused the EG4 inverter to go into Battery Protect mode. This is why it may be worth the $$$ to have batteries the inverter can communicate with. I know this from using the same battery in our art studio shed, and tweaking it to get the automatic transfer switch to kick on correctly, before the dumb(but solid) RoarBatt inverter shuts off the power.

Here, I am at least now, not bringing in Grid backup, so I'm assuming I just need to push the Inverter output low voltage shutoff farther out until it's where I need it to be.

We did get to over 11kW of output today though, and almost 9kW in 3.8 hours of charging into the Lightning, and I didn't turn the system on until 8am. I think we'll get a few hundred watts out of the 7am-8am period, and we would have picked up, likely, another 1500-2k watts if the inverter had stayed on past 3:30pm. We're back to clouds for a few though, so it won't be as static of a test environment for awhile.

We also have some unfortunate shading due to the powerlines above the array for about an hour at the top sun time, 1:15 to 2:15pm. You don't think about how much shading messes with output until you see it on a graph(one of those grid boxes, is approximately 250kw). I'll probably play with software adjusting the panels somehow just for fun and see how much I can adjust out of that, while also tracking the juice the actuators use to do it. It'll be fun. I could also play around with the panel configurations, and add more series, to reduce the shading affect, but I'd probably want to add two panels so I could go 3s4p, then. The lines are also directly inline with the panels so adding series probably won't help my situation much, and it will be less of an issue in the summer, where the really deep trough probably won't happen, as that is the electric pole itself causing shading.

 

[MurphysLaww]

Pretty icky days the last few, so not much charging, but here is where we are at this point. We're starting our 7th day with solar assistant tracking and are now at 42.7kW generated and 32kW sent to load. For what has been a pretty cloudy period, I think I'm happy with that.

Used an angle tracker for the first time when moving the panels, and with the 18" current linear actuators, we are moving the panels 15 degrees from horizontal each way. We're currently signing the contract with with Progressive Automations for the Hall sensor 24" linear actuators, and we'll be shooting for between 20-25 degrees of movement each way with those.

Solar Assistant output

Ford Pass charge logs - I think we started charging with the system in the evening of the 10th. Solar assistant, was brought up on the 14th. We're not staying caught up due to the lack of sun right now, and will likely need to top off with the Chargepoint. We're probably not going to bring up AC backup, as this whole system is a proof of concept for when we might be in Central America with no grid-backup. It's possible we'd add a diesel generator, though. Short of that, though the goal here is refining the system to get the most output possible, and make it viable on it's own. We did this with the art studio, and it very rarely uses the automatic transfer switch now. We're still a ways away from the 15kw we'd like to get on a decent sun day, but may not see that until after the winter, as even on what looks like a full sun day, we have not had output above 3kw from the panels. The inverter can take up to, I think 7.5kw of panels, and 500v. We may add 2 panels, to even up the series vs parallel, and use all the input ports on the combiner.

Also, likely will be pulling my Victron Smart shunt out of the Art studio, and cutting it in to the system to monitor SOC a little better. Not sure yet, but might.

Starting to build out the controller for the smartgarden and solar tracking. I've done both of these systems separately, just combining them in one box this time. None of these components are finalized.

• The Round Arduino IOT controller will stay for the smartgarden irrigation controller and has all the monitoring, and the relays that control the rain barrel pump feed.
• The components on the yellow mount are a cheap mppt charge controller that will take the 100watt panel input I'm using to run this system, the little one is a DC power monitor, which will monitor the 18650 battery power supply, and then the DC buck converter that will take the solar 18v down to 12v to charge the batts, and power the arduinos.
• On the Green mount, is an arduino uno R4, which may be replaced with a giga-wifi arduino. The red panel is a Drok 7amp motor controller, but I think I will be switching to a higher amp controller, based on how much the Progressive Automation actuators need to move the panels. This one is a two port, and I currently have two actuators doing single axis movement on top of the art studio shed running off one port, so I think I could run at least 4 actuators off one of these boards. I might need an individual controller for each actuator, though, when I start using the positional control with the hall sensors in the Progressive Automation actuators.
• In and and out 12v fans to keep the box cooler. This was good for 10-15 degrees cooler in my current garden controller box. The arduino's I've been using get flakey around 125 degrees F, and since it can get up to 107-108 here now in the summer for days on end, this ended up being important.

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