The trick to bitcoin is solar and wind power. My friend has invested quite a bit into green energy and produces much more than his household uses. Using the excess electricity to mine bitcoins has been generating him quite a nice pile of money on the side, basically for free.
At this point he gets about $400 USD per week with very little effort or cost, and always saves the bitcoin he gets until there's an upswing in price, then he spends it. Some he spends directly, some he spends on gift cards (the Gyft app allows him to buy gift cards for basically any store including ebay and amazon, using BTC), and some he changes out to USD and puts in his bank. Some he keeps as BTC for the long term savings.
At this point he's made over $100k. For a UPS delivery driver with a family, that's nothing to shake a stick at. At first he used standard electric company power at $0.13 per kWh, but the moment he had enough for a large green energy upgrade, his profits really took off, and his pollution heavily dropped. Were it not for Bitcoin, he would never have been able to afford the switch to the large Solar and Wind setup he currently has. He even generates a bit more electricity than his household (including Bitcoin Miners) use, and he sells this excess back to the electric company. Instead of a monthly bill, the electric company sends him a monthly check, paying him for his extra electricity.
He's also already been able to help his neighbors more than once when they lost power due to financial troubles or electrical storms.
If one day Bitcoin were to suddenly drop like a stone and fail completely, he'd simply sell the energy currently used by his Bitcoin Miners to the electric company and his monthly check would be larger. The very definition of win/win.
[doublepost=1514914406,1514912957][/doublepost]Personally I think anyone mining cryptocurrencies should invest all profits into building renewable energy systems that can handle the load ASAP. Not just for altruistic reasons (though less pollution is always better) but even simply for greed: to maximize profits. The ROI on renewable energy is pretty long term, normally, and that bars a lot of people from making the switch. Crypto Mining hastens that ROI by leaps and bounds and can provide the financial means to make the switch all by itself. And there's something really cool about not only being the only house with power during a storm or outage, but having the excess available (once you switch off the miners) to power some of your neighbors as well. Or getting that monthly payment from the local electric company for your extra electric.
Also there's all the little things. Like having outdoor outlets available for anyone to charge their stuff for free. Like having enough battery power always in the house batteries to jump start a car. Like being able to unplug a few of those batteries and take them camping. Or take a couple on his boat.
He says his next upgrade will be an electric vehicle, probably a Tesla, so that he doesn't have to buy gas anymore either.