What Is Proof of Work?
To add a new block of transactions to Bitcoin's blockchain, miners must solve a mathematical puzzle. This requires significant computational power and therefore electricity. The first miner to solve the puzzle wins the block reward, currently 3.125 BTC.
The "proof" is the work: Anyone can verify that a miner did the computational work — it's mathematically provable. This proves no one cheated.
Why Does Bitcoin Use Proof of Work?
The core problem: In a digital system, how do you prevent someone from spending the same Bitcoin twice? Traditional systems use banks as trusted intermediaries. Bitcoin uses math.
PoW solves this by making attacks expensive. To rewrite Bitcoin's transaction history, an attacker would need to redo more computational work than the entire honest network — requiring billions of dollars of hardware and electricity.
Energy consumption is security. Bitcoin's energy use isn't waste — it's the cost of trustless, censorship-resistant money.
Proof of Work vs Proof of Stake (Ethereum)
Ethereum switched from PoW to Proof of Stake, PoS, in 2022. In PoS, validators lock up cryptocurrency as collateral instead of doing computational work.
The tradeoff: PoS uses less energy but introduces different attack vectors and centralization risks. Bitcoin intentionally remains PoW because its community believes the security model is more battle-tested.
What This Means for Canadians
Canada has significant Bitcoin mining operations in Alberta and Quebec due to cheap, abundant electricity. Bitcoin miners are effectively selling energy security to the global network.
For investors: Bitcoin's PoW-based security is one reason it's treated as digital gold — it requires real-world resources to produce, similar to mining physical gold.
