Blockchain, also known as Distributed Ledger Technology, is now well-known for powering a number of "hidden" digital money systems like Bitcoin. It also refers to a computerized procedure designed to make databases more equitable, transparent, and practically tamper-proof.
Although this is the intended result, there are still questions about whether the technology truly accomplishes its objectives.
Additionally, the method by which it achieves this casts doubt on its viability in a future where energy use must be constrained in order to combat global warming.
Why is it called a blockchain?
A blockchain's 'block' is a list of data that is accessible to the general public. This might be almost anything, including the specifics of a financial transaction, health information, or ownership documentation. It may be used by a select few friends, or it might be available for use by anybody in the globe.
Blockchain technology was created in the 1990s as a mechanism to guarantee that modifications to documents were securely time stamped. Only in 2009 did a programmer going by the alias Satoshi Nakamoto create a blockchain-based database for a cryptocurrency known as Bitcoin.
The idea uses a special identifier called a hash based on the contents of the document to provide a randomly generated code known as a nonce, which distinguishes it from most other databases and open documents.
When a block is modified, a new hash is generated, which is equivalent to a whole new block. A chain of blocks is called a blockchain when each new block has a reference to the hash of the block it was based on.
The method is, in theory, tamper-proof since each new block stores the previous hash. The hash of a previous block in the chain would likewise change if that block were to be edited, maybe to modify the ownership history or a value. Blocks farther down that chain would no longer link to it as a result, invalidating that chain.
How does blockchain technology work and why is it so controversial?
In practice, there are two ways to verify the legitimacy of each node in a blockchain.
For these computations based on each block's contents in permissioned blockchains, an agreement must be reached. The calculation of the following block is acceptable if the majority of copies in a chain concur.
Every time a new block is formed, permissionless blockchains necessitate a complicated procedure. The computations, which are referred to as an election process, are based on an intricate internal puzzle.
The development of new blocks should be slowed down as a result, but in reality, individuals with higher computational capacity are better able to solve these riddles.
Why may some blockchain operations be hazardous for the environment?
No matter what sort of blockchain technology you employ, requiring a computer to perform a proof of work calculation for every new block uses energy.
This might not be a huge problem normally. But in the case of well-known cryptocurrencies, the process of creating new blocks, or 'mining', pays off. Each block mined yields the miner a modest amount of coins thanks to the economic principles incorporated into the permissionless network.
This makes mining cryptocurrencies profitable and encourages people to use a lot of processing power to do the complex computations required to crack the blockchain's riddle and extend chains.
The Bitcoin network managed over 26 quintillion (10 to the power of 18) hashing operations every second just a few years ago, in 2018. Although it is obvious that each one needs electricity to execute computations and keep the computers functioning, obtaining an exact amount relies on the types of mining equipment being utilized.
According to one estimate, Bitcoin consumed 2.55 gigawatts of electricity alone in 2018, which is nearly equivalent to the energy needs of a small country.
The Cambridge Center for Alternative Finance has also estimated that Bitcoin presently accounts for more than 0.5 percent of the world's electrical generation.
Of course, fossil fuels are not required to be the source of the power. The issue of energy consumption may become less important in a world powered by sustainable energy sources. Blockchain integrity changes, maybe including quantum encryption, might lead to the emergence of "greener" types of crypto-economy.
However, none of that accounts for the enormous volumes of e-waste produced by the sector, which for Bitcoin alone may surpass 30 metric kilotons annually, or about the same as the tiny IT equipment trash generated by a nation like the Netherlands.
As of right now, almost every new block added to the chain comes with a side serving of carbon and tons of hidden resources, making the burgeoning use of blockchain currencies a significant environmental problem in the years to come.