Recently, the Stellar Development Foundation (SDF) enlisted PwC US to develop a framework to assess blockchain protocols’ electricity consumption and emissions. The first-of-its-kind assessment framework informs and enables blockchain and financial services organizations to consider further measurement of their environmental footprints. The framework aims to quantify material environmental impacts of blockchain, building on existing research in the market.
Within the framework, SDF and PwC US give consideration to electricity use, greenhouse gas emissions, e-waste/embodied carbon, differences in consensus mechanisms, and areas for further research.
The Stellar network is an open source blockchain that has processed hundreds of millions of payments around the world since its launch. Over 200 entities including fintech companies, financial institutions, developers, and more leverage the Stellar blockchain for cross border remittances, credit service, NFT projects, and more around the world.
Applying the assessment framework to the Stellar network, the findings were that the electricity consumption and carbon emissions of the network are low. Via the Stellar Consensus Protocol (SCP), a low-electricity consensus mechanism achieved through proof-of-agreement and with no mining involved, the Stellar network currently uses an estimated 481,324 kilowatt hours (kWh) of electricity per year. This results in approximately 173,243 kilograms (kg) of CO₂ emissions per year — that’s the equivalent to the average CO₂ emissions produced by 33.7 U.S. homes’ electricity use in one year.
Despite the Stellar network’s already low electricity use, SDF supports sustainability throughout the network. SDF established a Carbon Dioxide Removal (CDR) commitment and will take the significant step to pay for the removal of the historical carbon footprint of the network since 2015. By removing the network’s unavoidable CO₂ emissions, they can no longer contribute to climate change. In line with its open source ethos, SDF will also work with ecosystem companies who choose to opt in to pay for the removal of carbon from the network on an annual basis going forward.
While there’s no perfect solution for addressing CO₂ emissions, SDF plans to engage with CDR efforts supported by many scientific communities. The latest Intergovernmental Panel on Climate Change report states that CDR deployment to counterbalance hard-to-abate emissions will be critical in order to reach global emissions reduction targets by 2050.
Access the assessment framework here. SDF hopes the framework serves as a foundation for ongoing research and conversations related to blockchain sustainability.