They say it is being adopted at a faster rate than the internet in the 1990s, with El Salvador having become the first country to adopt it as legal tender, alongside the US dollar, in spite of misgivings from the International Monetary Fund. Photograph: Elin HГёyland/The GuardianДЄdvocates for bitcoin argue that it offers the opportunity to exchange value with someone instantly without using a third party such as a bank, without permission and virtually for free. Kryptovault is transitioning to new ones from China that are said to be three times more efficient.

вЂњThat includes also traditional gold mining, which takes more than four times the amount of energy as bitcoin mining.вЂќ вЂњIf you look at the total energy cost, globally, for any given thing, itвЂ™s always going to be huge вЂ“ I think we can always compare to that of a small European country,вЂќ he said. Kjetil Hove Pettersen, 39, KryptovaultвЂ™s chief executive, who founded the company with friends after deciding to turn a hobby into a business, said he also believed it was time for the sector to push back at the prevailing narrative. It has been described by some critics as greenwashing, but within a world that has until now been less than transparent over its activities, preferring secrecy over sympathy, this was a shift. This week, the billionaire Michael Novogratz, the owner of Galaxy Digital, a digital assets company that seeks to become вЂњthe Goldman Sachs of cryptoвЂќ, launched a sustainability programme on energy use and social responsibility, saying the industry needed to tackle a вЂњfalse narrative around it being bad for the environmentвЂќ.

вЂњThe ministry of local government and regional development is currently reviewing potential policy measures in order to address the challenges related to extensive energy usage caused by crypto-mining.вЂќД«ut there is a fightback brewing in the sector, of which Kryptovault, which uses only renewable energy, is a part. вЂњAlthough crypto-mining and its underlying technology might represent some possible benefits in the long run, it is difficult to justify the extensive use of renewable energy today,вЂќ Gram said. NorwayвЂ™s regional development minister, BjГёrn Arild Gram, told the Guardian his government was reviewing its options. Swedish regulators have called for something similar in Europe. RussiaвЂ™s central bank has proposed outlawing all cryptocurrency operations in the country, and China has already done so. Photograph: Elin HГёyland/The GuardianДЇor many, at a time of rocketing energy prices, this may be further evidence of the unsustainability of a business that was recently described by Robert McCauley, a senior fellow at Boston UniversityвЂ™s global development policy centre, as вЂњworse than a Madoff-style Ponzi schemeвЂќ. Noise insulation at KryptovaultвЂ™s warehouse in HГёnefoss. Despite noise from ventilation fans so loud that the company had to spend about ВЈ1.5m on insulation after complaints from neighbours, the hot areas in the HГёnefoss warehouse can reach 55C.

The latest calculation from Cambridge UniversityвЂ™s bitcoin electricity consumption index suggests that as a result, the sector consumes more energy in a year than many countries, including Argentina, Pakistan and Poland. The company expects its mining to account for just under 1% of the computing and process power in the global bitcoin network later this year.Д«itcoin mining, the process of earning cryptocurrency by solving complex computational math puzzles and verifying transactions in the process, is famously energy-intensive. It is one of two such sites owned by the Norwegian company Kryptovault. The wood is being warmed by some of the so-called waste heat being emitted from thousands of stacked-high computer servers, known as miners, working away inside the warehouse.

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