Elon Musk has been named Time Magazine's Person of the Year for 2021.

"He's a player in robots and solar, cryptocurrency and climate, brain-computer implants to stave off the menace of artificial intelligence and underground tunnels to move people and freight at super speeds," Time Magazine said.

As implied above, the South African-born entrepreneur and Tesla CEO has made a series of crypto-related headlines this year.

After Tesla dropped half a billion dollars into Bitcoin in February, Musk famously u-turned on the flagship cryptocurrency after noting the damage it does to the environment. Musk has also frequently impacted the crypto markets owing to his interest in meme cryptocurrencies like Dogecoin.

Musk, Bitcoin and the environment

Perhaps his biggest contribution to the crypto industry this year has been his (in)famous u-turn on Bitcoin.

In February, Tesla invested $500 million into Bitcoin, adding untold momentum to the flagship cryptocurrency's institutional momentum already being fuelled by other companies like MicroStrategy and Square.

But just three months after that huge Bitcoin bet, Musk took to Twitter to announce Tesla's policy reversal.

"We are concerned about rapidly increasing use of fossil fuels for Bitcoin mining and transactions, especially coal, which has the worst emissions of any fuel," Musk said. He added that "Tesla will not be selling any Bitcoin and we intend to use it for transactions as soon as mining transitions to more sustainable energy."

Musk caused immense controversy on Bitcoin Twitter at the time, but he was right. Bitcoin uses an immense amount of energy—comparable to some of the world's most energy-hungry countries—to function.

Since then, a renewed debate about Bitcoin's carbon footprint has emerged, which also saw the creation of a Bitcoin Mining Council to oversee Bitcoin's hopeful transition to renewable energy.

Musk and the crypto markets

Musk's u-turn on Bitcoin sent the cryptocurrency's price into nosedive, but it wasn't the only time Musk's tweets have moved the crypto markets.

As early as February, a study from the Blockchain Research Lab showed that Musk's public musings about Bitcoin and Dogecoin caused near-20% spikes for both cryptocurrencies.

This study generated an important debate for Musk—namely, should one man have the amount of power over the markets?

"Our results lead to the question under which conditions people in the public eye should comment on specific cryptocurrencies. If a single tweet can potentially lead to an increase of $111 billion in Bitcoin's market capitalisation, a different tweet could also wipeout to a similar value," Lennart Ante, Blockchain Research Lab researcher previously told Decrypt.

Elon Musk the contrarian

When he's not raising awareness over Bitcoin's impact on the environment or tweeting about Dogecoin, Musk has weighed in on other big topics in the crypto space.

In September, Musk said the United States government should "do nothing" when it comes to regulating cryptocurrency.

"It is not possible to, I think, destroy crypto, but it is possible for governments to slow down its advancement."

He also took aim at the Chinese government for its crackdown on crypto.

"I suppose cryptocurrency is fundamentally aimed at reducing the power of a centralised government. They don't like that," he said.

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