There are about 2000 less or more cryptocurrencies available in market and daily 24 hours computers or computer farms or running to produce the cryptocurrencies or bitcoin and more than a half of these farms are running in china to produce bitcoin or cryptocurrencies.
To produce cryptocurrencies tens of thousand computers are linked together to solve complex mathematical equations and in return they are rewarded with a cryptocurrency.
Recent study shows that that world have consumed about same energy as of any countries energy consumption.
In 2015 Denmark consumed energy about more than 30 billion kwh ( kilo watt hour ) whereas the mining of cryptocurrency bitcoin in 2018 also consumed energy about the same level or a 1 billion kwt less than Denmark.
However cryptocurrencies are virtual currencies or digital curries it doesn’t mean that it doesn’t cost anything to produce. Cryptcurrencies.
To produce a bitcoin or Ethereum or Litecoin or Monero it requires energy about 17 or 7 or 7 or 14 MJ ( Mega Joule ) respectively and it’s the cost or energy more than producing or digging precious metals like gold , platinum , copper etc.
A Joule is unit of energy and it’s defined as when a force (1 Newton) applied to move an object for one meter distance or in other words we can say that one Joule of energy is equal to one watt.