Yes, i agree bitcoin is using too much of energy, one of my friend had a big problem about paying bills, because it is expensive. He uses too much electricity.
Your friend mine bitcoins? if yes that bill must be covered by the profit generated from that mining. if your friend not making any profit that means you mine the wrong cryptocurrency, just saying out there like a ton of cryptocurrency you can mine and probably gonna make more profit than mine bitcoin.
There are actually multiple possible reasons:
1.
He's mining using the wrong device. Some people wants to try bitcoin mining and start using their PC or their laptop right off the bat without computing how much money they will be making from it and would it be more than what they are paying for the electricity bills, internet bills, and if it's really worth over-stressing your computer. Your computer should be made specifically for mining and not just a regular computer in order for it to be economical unless the electricity is cheap in your country.
2.
Electricity is NOT cheap in your place. Honestly these days is electricity even cheap anywhere? Almost everywhere it's expensive and if you are dead serious with mining and it's okay for you to move to a foreign country (where electricity is cheap) to mine bitcoins, then go ahead. It's possible that you have a good setup for a mining rig but still lose money because the electricity is just so expensive.
3.
Bitcoin's price went down when he was just about to pay for the bills. Self-explanatory.
4.
You don't have a decent enough mining rig. The truth about mining is that people can't just mine and then be able to earn some bitcoins. I mean, we can do that. But it will not be practical since you will be earning less than the money you're spending. With the rise of more people mining bitcoins, it will require more and more computing power to have more earnings than your expenses.
I suggest that you guys check out this article from Forbes regarding the energy consumption of bitcoin mining:
https://www.forbes.com/sites/christopherhelman/2018/01/16/bitcoin-mining-uses-as-much-power-as-ireland-and-why-thats-not-a-problem/#35ff15824589