The only thing that's possible to run on solar panel in Nigeria is graphic cards, you can build a rig with 6 gpu and they whole rig will only take from 600watt to 750watt depend on the graphic card number,
This would be good advice if Ethereum Proof of work was still there, but we all know that that's now history, which means mining other altcoins will also not bring in the expected necessary profits, at least in this bear market.
Generally, it's a very risky venture and perhaps one that could have an ROI after a very long time. I am thinking by the time one is close to even getting the ROI, the mining gear they have could already be obsolete.