Cryptocurrencies and the blockchain are not a trend that will fade again. We are aware of this fact and that is why we have been considering the consequences.With the growing popularity of blockchain-based network services such as rendering, cloud computing, cloud storage or cryptocurrency mining, an increase in energy demand by computer centres can be observed. Fossil fuels are used to produce an overwhelming amount of energy needed for high performance computing services offered by the data centres, which has a negative impact on climate change.