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Blockchain, the cryptographic technology behind the digital currency bitcoin, could also be adapted for environmental purposes, such as guaranteeing that fish sold to consumers come from labeled sources, such as these salmon farms in Norway.

Andrey Armyagov/Alamy Stock Photo

Can bitcoin’s cryptographic technology help save the environment?

If you’ve heard of bitcoins, it may have been in the context of people using the digital currency to pay off ransom demands for the contents of their hacked computers or buy drugs on the dark web. But the underlying cryptographic technology, a growing chain of time-stamped records or “blocks” that is shared between many computers, forming a “blockchain,” could also be used to help save the environment, according to a commentary published today in Nature by Guillaume Chapron, an ecologist at the Swedish University of Agricultural Sciences in Riddarhyttan. Science spoke with him about the future of money, the government, and trust. This interview has been edited for brevity and clarity.

Q: What is a blockchain?

A: The blockchain—by which I mean the technology underlying all blockchains—is a protocol to build an immutable ledger, a database of transactions. You could say it’s a kind of decentralized supercomputer that creates trust.

Q: How can it help the environment?

A: Environmental problems emerge because we lack trust. The environmental crisis grows in a fertile ground, which is the multiplication of intermediaries. To take an example, if you buy a fish at the supermarket, the supply chain is very long. The supermarket might not even know where it came from. And so there are multiple opportunities for environmentally unsustainable goods to enter the supply chain. A blockchain-based supply chain would mean that when you buy a fish, you scan a QR code [like a bar code] with your smartphone, and you see every step. And you know that it cannot be falsified.

The blockchain can also change how we treat ownership. In many developing countries, land rights are not properly defined and a government or a company could claim a land that is owned by a local community. So if we were to put a land registry on the blockchain, it would be immutable. We could not falsify that land registry.

The blockchain can also influence policymaking. Blockchain voting is a very cheap and secure way of organizing elections. Now, if you want to organize an election on how to manage a natural resource, whether it’s a forest or fishery, you need to plan the infrastructure, you need the ballot boxes, you need to tell people to go out and vote that day. That takes a lot of money, a lot of time. And in the end maybe people may not trust the results. With a blockchain, you could vote with a smartphone and your cryptographic identity and achieve strong security.

The fourth way is by changing incentives. A blockchain can ensure that an event will happen. That sounds a bit strange, but if you put a contract on the blockchain, you can include business logic as computer code. When a condition is met, the contract will be automatically executed. For example, we could have satellites remotely monitoring biodiversity, and if we reach a certain amount of biodiversity in an area we could reward the local community with immediate and direct payment. You could say, “How are you going to pay communities if they don’t have bank accounts, which is the case for about 2 billion people on the planet?” Then comes the blockchain again. They can simply create a bitcoin wallet as soon as they have access to the internet.

Q: Are there downsides to the blockchain?

A: There are several downsides. The first one is that the blockchain is still slow. It handles seven transactions per second, compared to 2000 for the Visa network. And then the big irony is that the blockchain is a giant sucker of energy, consuming almost twice that of the whole company Google. What’s needed is to develop a more energy-efficient algorithm. Another disadvantage is, if you have a bitcoin wallet and you lose your private key, your digital signature, then your bitcoins are lost forever. What we need is to hide the cryptographic complexity in smartphone apps.

Q: Are a lot of ecologists interested in the blockchain approach?

A: I’m not aware of any other academic papers that link the blockchain to how it can help the environment. We need more development. We have FinTech, which is using new computer technology to help the financial industry, but I am proposing the term SusTech, which is using new technology like the blockchain to help sustainability. And the other that has not been much mentioned before is cryptogovernance. We have cryptocurrency, like bitcoin. What I propose is to explore governance that relies on cryptography, through elections and contracts. When people understand more and more what the blockchain will allow, they will have more and more new ideas that we can’t imagine today. My paper is intended to stimulate thinking.