If you don't have any mining equipment, then your options are even more limited. Keep in mind, even with free electricity, buying a mining rig will only pay off if the price of BTC goes up. This means that miners who buy equipment are basically betting that the next bull run will happen.

Given that you mentioned the ability to sell excess electricity generated, the best solution would be to do so and use the funds to purchase crypto. This approach allows you to indirectly participate in the cryptocurrency market without the need for mining equipment, thereby potentially capitalizing on the market's movements.