Actually mining costs are one of the biggest problems of bitcoin. According to a new study of Oak Ridge Institute in Cincinnati, Ohio, the amount of energy required to mine one dollars worth of bitcoin is more than twice that required to mine the same value of copper, gold or platinum.
It also happens with other cryptos, but the amount of energy required is lower that the bitcoin does.
In the long term, the environmental impact of cryptocurrencies will vary not only with their market value, but also according to the adoption of new technologies.
I think new and advanced types of processor technology can lessen the need for power and this will be a big step to keep mining profitable.
I read that the price of bitcoin can not fall below a certain amount, since the high cost of electricity. I also know that the stellar blockchain is ecological ( energy-consuming ), that is realy ?