r/SolarDIY

So I spoke to someone in solar sales and they told me that the battery usually doesn't cover the full night. It might reach up to half of the night but not the full evening.

This is how she explained it and how Claude explained it, it's like a pump and a water tank, you can't just have a bigger tank, you need a bigger pump to fill it too. Which I understand... then why don't we get that bigger pump? And now I understand there are cost limitations to that.

But I thought the whole point of sizing to your electricity bill and your day/night usage is to cover that electricity?

Maybe I'm missing something, maybe this is a highly optimal set up or a standard that works? Idk.

Anyway, this has been a concept I've been struggling with for a while. If anyone can help me understand, with a different perspective, that would be so helpful 🙏

For context, I am adding three 200 watt, 31 volt panels to the roof of an off grid cabin. Electrical codes are not an issue. I'm planning on 10 AWG stranded, but which kind? There are lots of 10 AWG choices on Amazon (I need this by Tuesday). I also understand that PV wire is preferred at least where the wire is UV exposed. But where it is indoors or inside conduit, is there any reason to prefer PV wire over something like marine grade triplex of equivalent gauge?

Hi I saw the prices of used solar panels and inverters and got the idea to try and make a simple 1-2 panel EV charger that should mostly cover all the energy the car needs. I wanted to ask some questions before I buy anything to make sure I have the right idea.

I know I need the panels a battery and an inverter and I think I also need a charge controller from what i understand the charge controller will stop the power from going into the battery if its full. I also know once I choose the panels I need to make sure I have the correct inverter and charge controller that can handle the max power the panels produce.

But after that I just connect panels to charge controller, controller to battery, battery to inverter and then plug in the EV charger? It seems simple but i just wanna make sure I'm not missing anything or if there's an easier way. I know solar makes dc and battery's charge in dc so maybe there's a way to cut out the inverter but that might get to complex for me since the ev charger itself plugs into a ac wall outlet.

let me know any flaws or concerns with this idea thanks!

Youtube caught wind of some research I was doing on whole-home surge protection

For fun, I watched it, immediately skipped over a ton of the blathering nonsense and found that they're worthless for actual protection on a home and pointless for a car.

I installed two SunnyBoy 6.0 (SB6.0-1SP-US-40) inverters in my 40-panel, 13 kW system about five years ago. No problems up until about six months ago, when one of the inverters arc-faulted.

I am extremely familiar with the entire installation because I built it all myself. It's a ground mount system, which makes it relatively easy to maintain. I am an engineer with experience in aerospace, robotics and other domains. The point being, I am well qualified and have decades of experience in electronics as well as high voltage (over 20,000 VDC) electronics.

I have never in my life experienced something as frustrating as SMA support. I don't know if they are badly trained, but their system is horrifically bad. It seem designed to impede support, frustrate people and have them leave or go spend thousands of dollars unnecessarily.

I have done all of the troubleshooting many times over and documented it all. I also brought in and paid a service tech (probably not SMA certified) to confirm my findings: One of the inverters has a problem and has to be replaced. Nothing else can be the problem, not the panels, not the wiring to the array. It's the inverter.

They put me through the wringer. They asked for logs. I sent logs. They asked for resets and then logs. I reset and sent logs. They asked for thermal images (they probably thought they had me there) and I grabbed my FLIR camera and sent them thermal images. I delivered everything they asked for and then some. Data. Pictures. Tests. Logs. And a report from the technician.

And then they say (paraphrasing): If this is going to RMA you need to have a corporate account to ensure you are certified or we cannot RMA the inverter. This, after days of frustrating back-and-forth, impossible phone calls, techs cutting leaving the chat while I was waiting for the inverter to reset and boot, etc.

While I was a happy customer. Sometimes the most important thing is what happens and how they a company treats you when you need help. This is absolutely not how you treat customers. I am not sure if this is a cultural thing (it's a German company) or what. There is simply no way I can ever recommend anyone use any SunnyBoy product. I you do, just be aware that, when you have a problem, and you will eventually, they don't have your back and they will make it as difficult and frustrating as possible, to the point that I told my wife the other day that I wanted to go to the DMV to experience good customer service (imagine that sentiment).

The only way they will learn is if they lose business. Don't buy their products. Period.

I'm putting together a little solar street/yard light setup and could use a sanity check on the charge controller.

Here's what I've got:

• 12V system, LiFePO4 battery, roughly 40Ah (~512Wh)
• 90W solar panel (standard 12V-class, Vmp ~18V)
• 30W LED load, so about 2.3A draw when it's on

I want a proper MPPT controller (not PWM — seems like I'd lose a chunk of the harvest at these wattages). I'd expect around 6–7A of charge current, so a 10A unit should give me decent headroom.

The one behavior I do need is basic dusk-to-dawn: when the sun goes down, the light comes on; when the sun comes back up, the light shuts off and the controller goes back to charging the battery. That's it — no dimming, no timed steps, no motion sensing. Just on at dark, off at light.

Beyond that, I want something that handles the fundamentals well: MPPT charging from the panel, sensible battery management for LiFePO4 (correct charge setpoints, and a load output to run the LED.

Any recommendations for a reliable unit in this class? any extra functions are nice to have but not a must

Thanks

I am a home owner and I have a grid-tied rooftop SolarEdge system. I live in an suburb area in northern California (a lot of sun). My area's electricity is quite stable and if it had an outage it was normally for only a few hours. However there are still some natural threats, such as winter storms and wild fires, which could damage the infrastructure to the whole region. Because it is rare and I only need keep essentials such as my refrigerator running, I don't want to spend a lot of money. Currently those "solar generators" are quite convenient and in low cost. Is there a way to utilize my rooftop solar panels to recharge a solar generator in case of a long power outage?

BTW, I am kinda handy with an electrical engineering background. I have being thinking going to the roof to run a wire directory from a solar panel (rated 330w), bypassing SolarEdge Optimizer, to feed into a "solar generator". How hard is it? It seems all the solar panel wires are hidden in the tracks. I hope there is a more elegant way anyway.

PS, I am on NEM2.0, so going to commercial solutions, such as Tesla Powerwall, is not attractive to me.

New to solar and I think I understand it but wanted to confirm. I bought one of the last Oupes 2400(orange sides) to offset the a/c electric bill during the summer/day. Not the best unit and I wouldn't buy another one since I can't add batteries and the long 6.5 hour charge time but here I am. I bought Two Dokio 400W 31V Panels and a Midea 8Kbtu "U" inverter a/c. I tested this setup with an old 5Kbtu unit and got 8.5 hours of run time before hitting 5%. The 5K drew 450 watts and the new Midea should draw 335 watts per the videos I watched. My problem is I only get about 6 hours a day of good sun and they only produced 580 watts but were just on the ground at at angle.

My plan is to run the Midea from 10am to 6pm on the unit but with the restricted sun hours it won't charge while running that long. I think if I add 2 more panels and add a MPPT to throttle the panels so I have 450-475 input watts at each Anderson input(500W max each) I should finish the day with about 60% or more charge and that would be enough to use the next day before the sun hours hit. I have sun from 11am to 5pm.

So the question is: Can I use a MPPT for this plug and play unit?

My local utility has an EV program that lets you run anything in your house from 10pm - 5am around .05 cents a KWh. They can’t distinguish or care what you’re charging, so that got me thinking why not charge whole home batteries overnight to use during the day.

I’m sure eventually the program will end, at which point I can prepare with building out the rest of the solar system.

Thoughts? Anyone else do this? What am I missing?

Hello Reddit.

I just got 25 solar panels. A solar installer went out of business and was offloading them. Right now I have an 8.5 KW, ground mount, grid tied system. It was installed by a professional company and is working great. Since I got the solar, I got an electric car and started heating/ cooling my garage so my power bill has gone back up.

I’m wondering what the best way would be to add some solar to my garage to help take the edge off charging my car and running the HVAC.

A few things I am concerned about:

-I have a really good net metering contract right now. I don’t want to risk resetting that because they don’t offer it anymore.

-I don’t want to risk any warranty loss of my current solar setup

- I want to keep it cheap. No point in saving on electric if I spend $10k setting it up. I already saved on the panels so I am hoping to do the rest for a reasonable price.

Any tips on how to integrate some of these new panels would be greatly appreciated