Slate Charging from Home Solar

[sodamo]

Would like to expand from another thread - Aptera-style solar panels in SUV option.

I will get back to that relevance later.

I have inferred that perhaps my knowledge/experience with home solar electric may be deficient. Perhaps info below will reassure and maybe even prevent someone posting to educate re pre basic solar information.

I am not an electrical engineer, nor a solar engineer, actually not an engineer at all, but solar electric is my life, not a hobby. I check the status of my system every day, whether in person standing in front of it or remotely via internet if I’m away. No power, means no water, no internet, nothing in house works, no happy wife.

Back in 2003 we bought property for our future home. Initial estimate was about $60k to bring commercial power to property. That only guaranteed having a forever bill in $200-300/month range forever and the reliability of the service (or not). Neighbors had off grid solar. We needed power to live in cottage we built while building our house.

My 1st system, 2005 was right out of Home Power magazine. 4 PV @ 120 watts each, charge controller, inverter/charger and some monitors assembled from Ebay, and a bunch of the largest 12 volt deep cycle batteries Sam’s Club had. A neighbor helped acquire rest of components locally and helped to wire. Not worlds best system, but it worked. Unfortunately, too much battery for too little PV. Lead acid batteries go down hill quickly if not properly charged. I soon added a 400w wind turbine. While pleased to see the led glowing at night, I never saw a plus up on battery meter. I added 2 more solar panels, an Outback charge controller, new 6 volt golf cart type batteries, upgrading system from 12 to 24 volts. Worked dependably for a number of years. Those same panels now power a DC pool pump.

During this time we started building our house and in 2007 turned on 48volt Outback based system, 4.5kw of 125w PV ($700/panel those days)with 2 Outback CC, 2 FX 3048 inverters, 3 kw each, 12 Rolls Surette 4v premium LA batteries and associated meters and controls to make it as much an integrated system as possible. I assisted in the design and install of this system so to be able to self maintain. Could have bought 2 Slate trucks. Over next couple years I added more PV, 2 more CC, 2 more inverters, undated controls and meters until I could actually monitor and control via internet. Was able to deinstall the cottage system and power from the house system. 2017, RS batteries started showing age, almost 10 years old. I researched alternatives and at urging of local supplier installed 21 Aquion saltwater 48v batteries. Within months, that Obama company went bankrupt and the professor went back to teaching after selling to Chinese company. Less than 2 years later was running generator hours per day inspite of upgrading all the old PV to 14kw. Nov 2017 I replaced the Aquions with 12 SimpliPhi 3.8 kw LiFePo batteries. Later that month I assisted my installer replacing the FX system with a new Outback Radian, 12kw system. Had intended to do it myself but his installed price was better than my equipment only price. Two years ago, I built a new PV array of 4.4 kw and added 3 more SimpliPhi LiFePos for a total of 57kw. We have a very robust system. This winter I upgraded to 16kw of inverters. Daily use is around 35kwhr, more if running the hot tub.

The heart of system. Before latest upgrades. Newest 12 PV array, 3 batteries, and a few assorted pieces not showing. Need newer pic.




I think these batteries would take up too much space in my Slate bed


The latest PV upgrade is basis for my potential Slate charging as I would/could divert that solar to charge the Slate, but HOW? Hence my Aptera interest.

Traditionally, a home solar system, be it off grid or grid tied will include at minimum, PV array(s), Charge Controller (s), Inverter (s), battery if off grid, or hybrid, and some controls and monitors. Now there are some newer, Chinese All in One systems, SolArc and Fortress are two, where everything except battery is in a single box. I have read where some can run without battery, but I think that has to be grid tied, not sure, but system has to be powered somehow.

Aptera connection.

So I can charge EV using my traditional system, but that would add about 20kwh daily load and my preference is not to add that stress to system/batteries. So my hope is find the black box that could connect to my excess, diverted PV power and directly charge EV. Aptera FAQ indicates they have that piece. So far I cannot find nor anyone else identify such a blackbox. And of course that could allow for off site charging with portable or Slate mounted PV.

Possibly could add an All in One, but that would be another $3-4K not counting Level 2 charger. Doesn’t seem cost effective and more to maintain.

Another alternative could be Bluetti. Their Apex 300 will accept 4k PV via an adapter and output 3.8kw of 240 v, 16 amps. Cheaper than All in one and even portable With or without PV.

If anyone has appropriate input/discussion I’m all ears. If you wish more info on my system, can answer that as well.

 

[Neil Nelson]

Not sure why you would need to put batteries in the back of your Slate since it already has batteries. You just need a device to output 120 or 240 volts, preferred, to Slate from your PV input. I doubt trying to charge a 52.7kwh battery from a few solar panels will be enough. Your house system outputs 35kwh and is fairly large.

 

[metroshot]

If you have solar, either get a Tesla battery for charging using the excess PV energy and then use a L2 charger to your Slate.

Otherwise use a portable battery pack like the EcoFlow that I have with 240V output and can be charged from home solar, home grid power, L2 public charger, or portable 400W solar panels.

 

[OldGoat]

I knew we would eventually end up with two EV's and also saw local utility company was getting permission for one price increase after another.
Sodamo's route for solar is quite different from mine. I used a vetted solar specialty company to do everything. After tax break the cost was about $38K and we have a modest battery backup installed. On decent days we generate 36-41 kwh. so we sell a tad to the grid and battery bank the rest for night time. If not running AC or dryer along with other heat generating appliances we use less kWh and essentially charging the Mach E is free since we only have to charge on average every five days. Our solar generation system requires we do absolutely NOTHING which is fine by me. If there is a grid power outage, I don't even have to throw a switch and several times I wasn't even aware of the outage if it's only a few hours. Uh oh....I lied. I do scrape snow off the solar panels in the yard sometimes since I don't want to wait for the sun to melt it off. That's why mine are in the yard, not on the roof.

 

[sodamo]

Not sure why you would need to put batteries in the back of your Slate since it already has batteries. You just need a device to output 120 or 240 volts, preferred, to Slate from your PV input. I doubt trying to charge a 52.7kwh battery from a few solar panels will be enough. Your house system outputs 35kwh and is fairly large.

Sorry, poor attempt at humor. Didn’t mean to suggest I’d disassemble my home system to charge my Slate.
No job for me at comedy club ☹

 

[sodamo]

If you have solar, either get a Tesla battery for charging using the excess PV energy and then use a L2 charger to your Slate.

Otherwise use a portable battery pack like the EcoFlow that I have with 240V output and can be charged from home solar, home grid power, L2 public charger, or portable 400W solar panels.

I wasn’t aware a Tesla battery could directly power a Lever 2 charger. When I had version 2 Tesla batteries reserved they still required an inverter. thank you.

 

[sodamo]

I knew we would eventually end up with two EV's and also saw local utility company was getting permission for one price increase after another.
Sodamo's route for solar is quite different from mine. I used a vetted solar specialty company to do everything. After tax break the cost was about $38K and we have a modest battery backup installed. On decent days we generate 36-41 kwh. so we sell a tad to the grid and battery bank the rest for night time. If not running AC or dryer along with other heat generating appliances we use less kWh and essentially charging the Mach E is free since we only have to charge on average every five days. Our solar generation system requires we do absolutely NOTHING which is fine by me. If there is a grid power outage, I don't even have to throw a switch and several times I wasn't even aware of the outage if it's only a few hours. Uh oh....I lied. I do scrape snow off the solar panels in the yard sometimes since I don't want to wait for the sun to melt it off. That's why mine are in the yard, not on the roof.

LOL, I guess for me old habits die hard. that and I do log performance in a spreadsheet. My walk out to the system also involves my dogs going with me as I keep a container of their treats on the bench. Should my wife survive me I have no doubt she will be like the 4 widows in our neighborhood who only see their system if a problem.
and with the newer All in Ones… just a couple weeks ago helped a friend mix and pour some concrete. Sitting around for lunch a friend of his commented he was having problems with Level 2 charging his recently acquired Chevy Bolt. he had recently moved he and like us totally off grid. When I queried about his solar system he only knew it was a box on the wall connected to some PV and batteries And it ran fine unless exceptionally bad weather. At least 3 of us somewhat aghast as 1 of us recently bought a PHEV, has an All in Ones SolArk and learned that unless he tweaked settings his system would go down when wife used the microwave. Guess people are beginning to get comfortable that newer systems just work. Progress 🤙

 

[OldGoat]

LOL, I guess for me old habits die hard. that and I do log performance in a spreadsheet.
Yeah I am guilty of also keeping a spreadsheet going back several years so I can see trends. Using a heater in the greenhouse was about the same as running a clothes dryer. You can see the little wings on your kWh's as they fly away. But home grown greens in winter made it worth it. As for monitoring the PV system the SolArk app is now excellent for making sure you are getting the correct performance out of your array.