,  CEO and cryptocurrency cheerleader, shook the crypto market when he said his company would . In a , Musk referred to an increase in the use of coal and other fossil fuels to generate the power used for mining as the reason behind his decision. The fallout from the tweet: binary options channel trading review The price of  and it continued to fall after. 

Bitcoin, Ethereum, and other popular cryptos reached record highs this year, raising concerns about the amount of energy needed to mine the coins. Warehouses of Bitcoin mining rigs run 24 hours a day, . As the energy bill for crypto mining rises, so does the amount of carbon and waste, adding to the growing climate crisis. 

Here’s what you need to know about crypto mining and its energy uses. 

What is cryptocurrency mining? 

When Bitcoins are traded, computers across the globe race to complete a computation that creates a 64-digit hexadecimal number, or hash, for that Bitcoin. This hash goes into a public ledger so anyone can confirm the transaction for that particular Bitcoin happened. The computer that solves the computation first gets a reward of 6.2 bitcoins, or about $225,000 at current prices. 

Other cryptocurrencies use similar mining technologies, contributing to the overall energy usage. 

What is a crypto mining rig? 

It’s a barebones computer with multiple graphics cards, or GPUs, instead of the single-card standard. Rigs usually use powerful GPUs from Nvidia and AMD to handle calculations and require high-wattage power supplies. The popularity of mining has led to a .

Why is crypto mining so energy-intensive? 

For starters, graphics cards on mining rigs work 24 hours a day. That takes up a lot more power than browsing the internet. A rig with three GPUs can consume 1,000 watts of power or more when it’s running, the equivalent of having a medium-size window AC unit turned on. 

Crypto mining businesses can have hundreds or even thousands of rigs in one location. A mining center in Kazakhstan is equipped to run . 

Not only do rigs take up power, they also generate heat. The more rigs you have, the hotter it gets. If you don’t want your rigs to melt, you need some cooling. Many mining rigs have multiple built-in computer fans. But if you have multiple rigs, the room quickly gets hot, requiring external cooling. Small operations, like those run by individuals, can get by with a typical standing fan. Mining centers, however, need a lot more cooling, which in turn requires even more electricity. 

How much energy does mining take? 

The estimated that one Bitcoin transaction takes 1,544 kWh to complete, or the equivalent of approximately 53 days of power for the average US household. 

To put that into money terms, the . That means a Bitcoin transaction would generate more than $200 in energy bills. 

Bitcoin mining used , according to an analysis from Cambridge University in February. At 121.36 terawatt-hours, crypto mining would be in the top 30 of countries based on energy consumption. 

Why is taking up so much energy bad for the environment? 

Fossil fuels account for more than 60% of the energy sources in the US. A majority of that percentage is natural gas and a minority is coal. The carbon dioxide produced by fossil fuels is released into the atmosphere, where it absorbs heat from the sun and causes the . 

As mining rigs consume more energy, nearby power plants must produce more electricity to compensate, which raises the likelihood that more fossil fuels will be used. States that have struggling coal power plants, such as , and crypto mining companies. 

What’s being done about this energy problem? 

Not much. The 3rd Global Cryptoasset Benchmarking Study from the University of Cambridge found that . Energy consumption made up only 30% of their choice. 

Access to renewable energy at a low price, however, attracts crypto miners. China’s Sichuan Province has the country’s second-largest number of miners due to its abundance of cheap hydroelectric power. Its rainy season helps to generate so much energy that cities are looking for in order to avoid wasting power. 

Musk said in May he spoke with North American miners, and . He then tweeted on June 13 that Tesla would allow Bitcoin transactions again if there was  which he listed at being approximately 50%. 

The operators of Ethereum, the second-most-popular behind Bitcoin, are doing something to change the amount of energy its miners consume. is an upgrade that will be completed sometime this year or in 2022. Instead of computers trying to solve computations — referred to as — computers will be randomly selected to create blocks for the blockchain, while computers that weren’t selected will validate those blocks created. 

To ensure miners do their job, each miner has to stake 32 Ethereum coins, also called Ether, which is equivalent to $85,000, hence the term for this protocol is called . This change reduces the amount of energy needed for Ethereum mining.

What other cryptos are more energy-efficient than Bitcoin?

A growing number of coins — there are more than 10,000 of them — use the proof-of-stake protocol that Ethereum 2.0 will transition to, resulting in a drop in power consumption. 

Cardano, for example, uses its own proof-of-stake protocol and consumes . To put that in perspective, Cardano’s energy use is a GWh and a half shy of providing enough power for the , with its , for a year. By comparison, Bitcoin uses , which is equivalent to the amount of energy Pakistan, with its , uses each year. 

Following Musk’s May 13 tweet, because it was seen as an environmentally friendly alternative to Bitcoin. Its on May 16, but its value fell and is currently at $1.57.