You can research which cryptocurrency is currently the most profitable to mine with your hardware and try it out for a month to see how much income you can generate. This will give you a better idea of the potential earnings from mining and help you make an informed decision on whether to continue mining or sell the extra power back to the electricity company. It should be a simple calculation after that. Either continue mining, or sell electricity and buy crypto directly with that money. Also keep in mind that mining can put a significant amount of stress on your hardware, which can lead to a shorter lifespan and more frequent breakdowns.