Bitcoin mining is energy-intensive because it relies on a “proof-of-work” system. Miners compete to solve complex cryptographic puzzles to validate transactions and add them to the blockchain. These puzzles are deliberately designed to be computationally difficult, requiring miners to use powerful computers and consume significant amounts of electricity. The first miner to solve the puzzle gets to add the new block of transactions and is rewarded with newly minted Bitcoin. This process not only secures the network but also incentivizes miners to participate. The difficulty of the puzzles also increases with more miners joining the competition, making it even more energy-intensive to solve. Essentially, miners are expending computational power (and therefore electricity) to prove they’ve done the work, hence the “proof-of-work.”