Dang I thought we found a real glitch in the Matrix to infinitely generate money XD I was like.. who's going to share that?! it's going to get patched XD

Anyway jokes aside it reminded me of how back hundred years ago, they'd get a coin, scratch some of the materials of it, and it keeps its value.
After a lot of "coin scratching", this person could sell those material, essentially got something out of nothing for free.

I've got my Rigs running on Timers running on/off automatically depending on the usual most active Solar Hours. ( Aka mine for free during the day)

It's impossible to answer your question without knowing how much Electricity you're consuming yourself!

200 panels is a big number, but it means nothing if you've got a lot of Asics & Hardware that will be consuming more than what you're producing!

1. Ask your friend (or look below the Panels if they are mounted/check inverter UI) how much each Panel is providing?

2. Panels will only produce as much as You're consuming + Battery Charging/inverter limit. ( If your panels can produce 30Amps, but your house is using 10Amps, and the battery is charging for another 10amps, those extra 10 amps will not be given to you by the Panels unless you are actively consuming Wattage)

3. For #2,  that is important to see if your friend is able to host your machines for you, what if his Solar Panels are not efficient for him + you together?

4. Obvious factors such as Time (there's no sun at night! ), and weather! -- Just because the Sun is up, it doesn't mean that your solar is 100% covering you! Even during the noon your solar panels might not be fully 100%

5. What if it's cloudy? You will now be using power from his Grid/Battery. - Will your friend's grid/battery be sufficient for YOUR MINING HARDWARE + His usage? or will it overload? (you can't manually be babysitting the rigs every second so you've got to take all these into consideration)

6. The "Sell to the Grid during the day & Buy Back at night" is one of the best due to point #2 I mentioned above, as that way you're ensuring that you're using your Solar's full potential.. but this isn't available for every town in every country in the world, you've got to see if you are able to do that, even if your system supports it.

7. Think about if it's going to be worth it for you, to put a big capital into mining, if you're only going to be able to turn it on for couple hours a day, and might not be everyday. (Rainy/Cloudy days etc)

- Solar Panels are cheap, and in 2024 today's Panels are way more efficient than 8-10 years ago. ( It's about if you have a spot for them, whether its a land, or on top of a building)
- Decent Inverters are affordable & fully customizable with modern feature that will fit your liking. ( I've got my Solar monitored by a Raspberry pi monitor near my mining rigs, whilst the inverter is in the garage.)
- Batteries on the other hand, you don't want to over-invest in, they do not last, their BMS might disconnect if you're not on Grid, they will die out before they could pay back, i would get batteries enough to support you through the Grid switching and Cloudy days, instead of putting a big capital into Batteries if you're wanting your own Solar.
This would atleast enable to start having few hours a day, almost everyday able to mine freely for certain amount of power range, for a very cheap intial cost!

TLDR; Check his inverter system, see if he got spare power to give you, and check how much power your own hardware is going to use. IF you mean "200w solar panels" you've got to count how many panels he got. You can't only go by how much he's getting maximum per day! (see point #2)

Aww hope you figure it out!!