Bitcoin

Blockchain enthusiasts tout Bitcoin and its cryptocurrency kin as decentralized digital assets, but the massive computing power required to maintain the digital ledger is heavily concentrated in a single country: China.

According to the Cambridge Centre for Alternative Finance, roughly 70% of the hashrate for mining Bitcoin—that is, the processing power for verifying transactions on the blockchain’s ledger —is generated in China.
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According to the Cambridge Bitcoin Electricity Consumption Index, the global Bitcoin mining enterprise uses more electricity than some entire countries, such as Argentina or Ukraine.