Attacks on Bitcoin’s energy consumption are mainstream by now. Negative takes come from politicians, other protocols that use Proof-of-Stake (PoS) or other actors that generally consider Bitcoin useless.

A quick survey of Bitcoin’s energy efficiency neutralizes many anti-Bitcoin arguments. Analysis shows Bitcoin is using less energy per block mined overtime, and therefore more efficient at securing the network.

History of bad calculations

Similarly to predictions of Bitcoin’s “death,” a cottage industry of sorts has developed around bad Bitcoin mining arguments.

For example, take an article from the World Economic Forum  written in December 2017 which argued Bitcoin would consume 100% of the world's power by 2020. Five years later, Bitcoin consumes only 0.16% of the world's energy production, according to industry group The Bitcoin Mining Council.

Or take Progressive stalwart and US Senator Elizabeth Warren, who claimed “A single Bitcoin transaction uses more energy than a typical US household in a month. I think the estimate is 53 day.”

These claims all have one thing in common by assuming that Bitcoin’s energy usage per transaction is linear. Critics tend to draw a line upward until Bitcoin is “using the world's energy” instead of digging into the efficiency changes made overtime.

Source: WEF

Network efficiency

Bitcoin’s energy usage continues to grow, but it's also becoming more efficient. On a software level, transactions and block packaging continue to get more efficient by stripping information from transactions without sacrificing security. One example is SegWit, a 2017 improvement to Bitcoin that allowed for numerous efficiency gains for Bitcoin.

Among other features, SegWit allowed the development of the Lightning Network which can move Bitcoin nearly instantaneously and freely. SegWit also made baselayer transactions more efficient, meaning each block can carry more transactions.

Today, SegWit transactions make up a majority of all transactions on the network.

Source: Transactionfee.info

ASIC improvements

Each new ASIC produced consumes electricity, but is becoming more efficient at consuming the same amount of electricity. The Antminer S19 is five times more efficient than the Antminer S9 and only a few years apart in manufacture date.

As the Bitcoin Mining Council recently noted, “Bitcoin mining is 5,814% more efficient over the last 8 years.” The council further concluded that the average estimated J/TH of a typical machine is 48.9 J/TH, a nearly 200x gain in efficiency since the first ASICs in 2013.

Read: How ASICs changed the mining game

Source: Bitcoin Mining Council

These technological improvements continue to make the Bitcoin network more efficient while maintaining security. Each block produced becomes more efficient over older blocks as the protocol evolves while each new miner plugged in is more efficient in its electricity usage.