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Comment by soggybread | Hacker News Reader

I'm just getting into Solar myself and while it seems like a lot there are some things that you have to do math for. If you've got 10 panels you'll want to find out how to get all that energy to the inverter/mppt without going over the volt/amp limit on the device. This is probably the most difficult part and for everything else there's a huge solar community of people starting exactly where you are. I myself just bought an Anker solar battery and 2 panels that I bring out during the day to charge the battery and it runs my laptop and monitor for the evening after I get home from work. I want to do more but I'm renting so I'm just trying to find ways to do so. When my state legalizes balcony solar you bet I'm going to play with that too.

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Its not difficult, you just have to change the configuration of your panels between in series and parallel.

Ideally you dont buy the all in one batteries as they usually have anemic solar inputs.

> without going over the volt/amp limit on the device.

It’s not clear what device you’re referring to in this context.

The MPPT solar controller.

MidNite has a sizing tool for this: https://www.midnitesolar.com/sizingTool/

So the most difficult part is using a calculator to determine the charge controller capacity.

No, you also need to calculate the voltage drop over your distance to show to minimum wire sizing, and the voltage and power levels at the ASHRAE minimum temperature, the current level at 156.25% over the wiring at the ASHRAE max temperature to compute the temperature adjusted resistance and show that your wiring meets minimum spec, etc.

It’s not too hard to actually do the computations. But there is a ton to learn. I installed my own 14.85 kW system last year, with batteries, and I spent hundreds of hours just researching everything. I know I went overkill, but the hardest part of the project was just getting up to speed on all the requirements to meet code.

Someday I’ll write up my entire experience and share my site plan I used for permitting in the hopes it will help someone else. But doing solar right is a nontrivial investment for a newbie (like me).

So the most difficult part is using domain specific online calculators to determine the wiring requirements and charge controller capacity.

The most difficult part is acquiring the necessary domain specific knowledge, including what your AHJ changed from the national codes. But yes, once you know everything it’s all pretty straightforward stuff.

No, just figure out how much solar you want and buy and accordingly sized charge controller/MPPT.

They will all tell you maximum input volts and amperage. You can calculate watts by multiplying those two and just need to wire your panels in a way that doesn't exceed either value.

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