The world is at a climate crossroads. Sustainability is not about a single point in time but the enduring state of a living and changing thing. Blockchain, the game-changing technology of this era, should also play a more proactive role in hastening this movement. While Bitcoin and Ethereum depend on Proof-of-Work (PoW) algorithms to operate, it is important to point out that there are important technical and design differences between blockchains that can deliver orders of magnitude greater operational efficiency.
In pursuit of our goal to cultivate a healthier planet through green technologies, the VeChainThor blockchain provides truly sustainable infrastructure for companies to build their smart contract solutions from. Using the highly effective and stable PoA consensus mechanism, VeChain solves the largest problem facing the energy use of a blockchain platform, that is, achieving consensus and updating the public ledger in an energy-efficient manner.
To build and maintain this successful practice, VeChain worked with Centre Testing International Group Co. Ltd.(hereinafter called CTI), the pioneer and leader in the TIC industry which provides one-stop solutions on testing, inspection, certification, calibration, audit, training & technical services, to measure the carbon footprint of VeChainThor public blockchain network.
According to the model, the total carbon emissions per year generated by VeChainThor is around 4.58 metric tons, approximately 2.4% of the carbon emission generated for mining a single Bitcoin according to [4, 5]. Total annual electricity consumption by VeChainThor is estimated to be 7581.31 kWh, roughly equaling the electricity used to process 4.3 Bitcoin or 51 Ethereum transactions [5, 6, 7]. We have also found the resource  that shows some data (in terms of the estimation of electricity consumption per transaction) of some PoS chains related to carbon footprint. The outcome was that each transaction on VeChainThor consumed approximately 0.000216 KWh, which was 0.04% of the amount estimated for Cardano as listed in .
To summarize the above, running the entire VeChainThor network for a whole year is equivalent to:
≈Only 2.4% for mining a single BTC
≈Processing 4.3 BTC transactions (electricity consumption)
≈Processing 51 Ethereum transactions (electricity consumption)
≈99.96% greener than Cardano at only 0.000216 KWh of energy for each TX on VeChain.
Rigorous Methodology of Carbon Emission Estimation
CTI is committed to deliver trust between government, enterprise and customers. CTI provides trusted authentication services, to combine scientific modelling and certified measuring to infer a reliable estimation of the carbon footprint of the VeChainThor public blockchain network. (Read Full Report)
Energy costs per transaction on a decentralized network are a preliminary step in determining whether a network can successfully achieve long-term sustainability. The VeChainThor blockchain is currently using the PoA consensus mechanism which does not require nodes to compete with each other in order to produce a new block. Instead, rights are equally distributed to all the 101 consensus nodes, i.e., the Authority Masternodes (AMs). Here the key finding is that the AMs share the same amount of computational workload in the network according to the design of the blockchain.
The next step is to define the scope of the carbon footprint for VeChainThor to make the task tractable in practice. It is reasonable to narrow down the scope to the AMs rather than covering all the nodes including those who do not participate in the consensus process. As a result, what we need to do is to deliver a model for estimating the carbon emissions of the 101 AMs.
To support the reliability of our estimation model, the measurement has to be designed based on some existing standards, strictly carried out and certified by CTI. It was found out that what we could do was to accurately measure the power usage of a single machine that solely hosted an AM in a controlled environment. Once we have the data, we can use the following model to estimate the carbon emission for VeChainThor:
Here EGHG stands for the amount of greenhouse gas (GHG) emission, PUE the average annual power usage effectiveness (PUE) for data centres worldwide , EF ii the regional emission factors (EFs) for electricity supply [2, 3], and MCTI the actual power usage data of a single AM measured by CTI. It can be seen that the model takes some important factors into account to reflect reality. For instance, it recognizes that a lot of the blockchain nodes may be hosted on cloud and the actual machines are maintained in data centres. Therefore, we use the average PUE data for data centres worldwide to estimate the amount of electricity used for maintaining all the machines. Moreover, the model reflects the fact that the carbon emissions for generating the same amount of electricity are different across regions. It therefore includes different regional EFs when estimating the overall GHG emission.
Green Entrepreneurship Powered by VeChainThor
A business’ digital carbon footprint is the complete expression of its operations. As the world's largest corporations such as Facebook achieve net-zero emissions and other giants such as Apple, Microsoft, and Google plan to aim for carbon neutrality by 2025, it becomes essential to raise awareness of how underlying digital technologies provide discrete yet vital roles for carbon mitigation and developing circular economies (UN).
As leaders in blockchain-based carbon reduction efforts and the driving force behind many sustainability oriented projects, we built a platform intended to become the most scalable, secure and greenest public blockchain infrastructure possible.
With the upcoming PoA 2.0 consensus mechanism upgrade, VeChain will provide an even more secure and efficient layer 1 public blockchain platform and combine it with high performance with almost neutral environmental impact. For enterprise users embracing their carbon reduction targets, VeChainThor is the perfect public blockchain choice for long-term enterprise collaboration.
 Data center average annual power usage effectiveness (PUE) worldwide 2007–2020 by Thomas Alsop, Apr 19, 2021
 Carbon Footprint Country Specific Electricity Grid Greenhouse Gas Emission Factors, by Carbon Footprint
 Document By The Ministry of Ecology and Environment, formerly the Ministry of Environmental Protection of the People's Republic of China
 Policy assessments for the carbon emission flows and sustainability of Bitcoin blockchain operation in China, S. Jiang, Y. Li, Q. Lu, Y. Hong, D. Guan, Y. Xiong & S. Wang, Nature Communications, 12(1938), 2021
 Comparing the Carbon Footprint of Gold and Bitcoin, Visual Capitalist
 Ethereum risks it all on going green, Fortune
 A single Bitcoin transaction has a bigger carbon footprint than 100,000 hours of YouTube videos, Business Insider
 Popular cryptocurrencies: Which is the most environmentally friendly?, TRG Data Centers