In 2009, the elusive Satoshi Nakamoto published a white paper about bitcoin. Shortly thereafter, the first bitcoin transaction took place. At the time, there was no estimated dollar value of a bitcoin. Fast-forward to December 2017, and bitcoin was trading at over $18,000 per coin.
While the bitcoin price has dropped substantially since that all-time high, the rapid ascent in value brought bitcoin into headlines around the world. In addition to bitcoin, thousands of other cryptocurrencies fit into a variety of niches, from the meme-based dogecoin to the anonymous verge.
All of these crytocurrencies have one major requirement in common: powerful computers to mine for new coins.
Bitcoin’s Energy Consumption
To begin to understand why bitcoin consumes so much energy, you need to know a few very basic concepts about how it works. Each time a bitcoin transaction takes place, all the computers on the network talk to each other to confirm that the transaction is valid. Once the transaction is confirmed as valid, it can proceed.
Some of the computers on the network are miners. They are responsible for grouping these transactions into blocks and adding them to the ledger. They do this by solving a complex mathematical problem. Once they’ve solved it, they are rewarded with mined bitcoin.
These math problems require computers with substantial processing power, which require a huge amount of energy to run. The Bitcoin Energy Consumption Index was created to track just how much energy bitcoin mining requires. According to their numbers, one bitcoin transaction consumes enough energy to power 31.75 U.S. households for a day (at the time of publication).
Currently, bitcoin’s estimated annual electricity consumption is 61.56 terawatt hours. That’s enough energy to power approximately 5.7 million U.S. households. That’s almost enough energy to power the entire country of Switzerland for a year. Bitcoin’s estimated annual carbon footprint is 30,162 kilotons.
Unfortunately, a high percentage of bitcoin mining operations are located in China and other locations where cheap electricity is produced by coal-burning power plants — thus worsening bitcoin’s overall carbon footprint. And while bitcoin is the largest cryptocurrency by far, thousands of other types of cryptocurrencies also need powerful computers, creating their own carbon footprints.
Most crypto experts agree that as cryptocurrency grows in popularity and usage, the energy needed for mining will only increase. As the math problems required to complete a transaction become more complex, miners will need faster computers with more processing power and a corresponding increase in energy consumption.
Can Bitcoin’s Carbon Footprint Shrink?
Despite some technical proposals to lower the processing power needed to keep the decentralized network running, the mathematical problems being solved must remain complex and resource-intensive to stay secure. However, some individual mining operations are trying to reduce their carbon footprint, or at least use renewable energy to power their computers.
One company, Qarnot, builds crypto-mining equipment that uses the heat generated by the computers to heat apartments and offices. Qarnot won the CES Eureka Park Climate Change Innovator Award in January 2018. Unfortunately, this technology is beneficial only in locations where it’s cold for a significant portion of the year. In hot climates, the heat generated would only necessitate additional energy to cool the building.
While bitcoin’s carbon footprint can be reduced, the big questions are how and by how much? In the short term, we can expect bitcoin’s carbon footprint to increase as more people join the bitcoin mining community. With time, however, we’ll likely see more advancements made to reduce the amount of power necessary to run a bitcoin mining operation.