The report estimates the relative contributions of coal, gas, hydro, nuclear and wind in the bitcoin mining industry at 35%, 24%, 21%, 11% and 4%, respectively.

The report found the carbon intensity of the bitcoin mining industry to be 466 gCO2/kWh, lower than the global average of 492 gCO2/kWh.

The report estimates the relative contributions of coal, gas, hydro, nuclear and wind in the bitcoin mining industry at 35%, 24%, 21%, 11% and 4%, respectively.

The report found the carbon intensity of the bitcoin mining industry to be 466 gCO2/kWh, lower than the global average of 492 gCO2/kWh.

In fact, some of the miners operate with a negative carbon intensity, as they mine with stranded natural gas that would otherwise be flared. The report shows how 1 unit of direct carbon emissions from this type of mining indirectly reduces carbon emissions by a unit of 3.7.

The 35% coal share of electricity generation for bitcoin miners is trending down, but still generates the vast majority of emissions (76%).

The natural gas share has increased lately since many miners have moved to the US, where a large percentage of the electricity is generated by natural gas. Natural gas generates approximately 24% of hashrate but only 21% of emissions.

Another popular energy source for bitcoin mining is hydro, which powers 21% of the bitcoin network against a 16% global average. Hydropower is an entirely location-dependent energy source. Therefore, bitcoin miners scour the globe for pockets of cheap, underutilized hydropower.