Enough with Bitcoin’s greenwashing ! Bitcoin runs mostly on fossil fuels.

Franck Leroy
Crypto Lucid
Published in
6 min readMar 9, 2021

By crunching the data, we find that the average carbon footprint of electricity used for bitcoin mining is 830g CO2 / kWh : Worse than the average US mix (530g CO2 / kWh). We should rise up against this madness.

As Bitcoin’s energy usage skyrockets along with its price, the Bitcoin industry (miners, traders, …) use a proportional energy to build legends for green washing. They invent a parallel world where burning phenomenal amounts of energy becomes good for the planet, in violation of the most elementary laws of physics.

You may already know that bitcoin currently consumes more electricity that Argentina, for processing only 0.02% of all digital transactions. This alone would convince anyone that Bitcoin is not serious and not physically sustainable. But advocates of bitcoin are still trying to minimize its environmental footprint :

  • “Bitcoin mining uses 76% renewables“,
  • “They use extra hydro water that would be wasted anyway”
  • “Miners seek cheap and thus “clean” energy …”

Really ? Let’s crunch the numbers :

Computing the average carbon footprint of miners

In september 2020, the University of Cambridge released the 3rd Global Cryptoasset Benchmarking Study : the most complete and up to date inventory of the Bitcoin industry. It provides a detailed analysis of the mining industry and the location of the miners.

On page 26, this report concludes that whereas 76% of miners declare using part renewable energies, those account overall for less than 40% of the energy used for mining :

Most miners are connected to the grid and inherit the carbon impact of the local electricity. The Cambridge University provides a detailed map of the miners, together with the share of each region. Most of the mining (>65%) is done in China. The footprint of the electricity in China varies widely between the provinces (either mainly coal or hydro power). Fortunately the map provides detailed shares by province.

By crossing this data with the regionalized footprint of electricity mixes provided by the ecoinvent database (life cycle footprint database), we compute the average carbon footprint of bitcoin electricity :

Table of carbon footprint for the bitcoin mining mix
Average carbon footprint of Bitcoin mining. Sources : https://cbeci.org & Ecoinvent 3.7

Overall, the average carbon footprint of the electricity used for bitcoin mining is 837g CO2 / KWh. Way worse than the USA mix (around 530 g CO2 / KWh).

The average carbon footprint of the electricity used by bitcoin is 837 g CO2 / kWh. This is worse than the US mix.

While Bitcoin supporters draw attention on the low-carbon hydro-powered regions (North America and Sichuan) they are clearly in a minority compared to regions with high carbon footprint.

Total footprint of Belgium, and getting worse

The same site provides a live estimate of the electricity consumption of Bitcoin. It is currently 130 TWh / year (more than Argentina). At 830 g / kWh, the total carbon footprint of bitcoin is thus 107 millions of tons of CO2 per year. This is worse than the total carbon footprint of whole Belgium (104 Mt CO2 / year).

And this is getting worse ! By looking at the evolution of the margin of the miners, we show that, after the recent rise, the total consumption of the network may still double in the next months, reaching the electric consumption of Australia and the whole carbon footprint of Argentina.

There is no clean / green energy

Bitcoin supporters still claim that this gigantic consumption is somehow good on the long run, because it will help to develop “renewable energies”. This argument is quite ridiculous : This is like saying Marlboro is good for health because causing cancer helps to finance research on cancer …

But let’s dig into this a bit more :

First, there is no green or clean energy. Renewables have a less (but not null) carbon footprint but they require (a lot !) of materials (metal, concrete, …) which are finite and very polluting to extract / transform. They also occupy a lot of land (which is finite and habitat for the wild).

Renewable energies

Also, climate change is not the only major issue humanity is facing. We are also running out of resources (some metals, sand, oil, ..) and we have triggered the 6th extinction of species in the history of earth, mainly by destroying their habitat. If you think drowning entire valleys to produce electricity is clean or ecological, think again.

In physics, the energy usage measures the irreversible transformations we do to the world. We do that at a pace that the ecosystem cannot stand. The earth cannot handle the carbon we reject in the atmosphere, nor clean the soils and water we spoil or produce again the resources we extract (sand, metals, oil, …).

The more we use energy, the more we extract, transform and throw wastes (in air, soils, …) : we produce entropy, and physics tell us it cannot be otherwise. We cannot increase the production / consumption of the economy while reducing our global footprint : this is a lie.

The goal is *not* to develop renewables per se

There is widely spread misconception that developing renewables is an ecological goal in itself. This is wrong. The goal is too reduce our global footprint (CO2 but not only, as shown above).

If you double the global energy consumption with 90% renewable, the global share of renewables will increase, but the net footprint will increase : the overall balance sheet is bad.

Developing renewable energies as a replacement for fossil fuels is a good thing. Developing renewables to increase the global consumption, especially for frivolous usages, is not.

In a world where the demand for energy increases, there is no transition: energy sources do not replace each other, they add to each other. In order to reduce our overall footprint, we have no choice but to stabilize/reduce our energy consumption and to switch to less polluting sources.

When the demand rises, energy source add to each other

Currently, the development of renewable energies can barely compensate for the growth in demand. Bitcoin makes it even worse.

Bitcoin has no place in this world.

At a time when humanity is simultaneously hitting all the physical limits of its environment (global warming, mass extinction, end of resources, …), such an astronomical waste of energy and resources is a crime. No matter what the hype and market say : Bitcoin, or any crypto currency using “proof of work” for securing its blockchain is physically unsustainable.

Bitcoin is not paying back for its impact either. A carbon tax would instantly kill it.

Bitcoin is 10 years old now and its technology is completely outdated. Other crypto currencies (etherum, nano, Chia, Ğ1, …) are using other security systems (proof of sake, web of trust, …) or are migrating to it. They offer similar characteristics (decentralized blockchain) with much less impact, and better performances for some of them (faster, lower fees, better privacy, …).

There is no rational reason to continue to support Bitcoin other than speculation. We should speak out against the use of PoW cryptos, calling for strong regulation and high taxes commensurate with their impact. This would be enough to calm down most institutional investors and precipitate the bursting of this speculative bubble.

Image of a coal mine reopened for bitcoin mining