The article uses Gas consumption as an approximation to measure the carbon footprint of transactions and provides data about the gas consumed on different kinds of NFT transactions.
For a specific marketplace, it mentions the following averages (Part 2 > Footprint per transaction type -- note: the article doesn't provide specific references at this point but it is packed with references and research and I believe it's based on the analysis of transactions for the smart contracts of that marketplace):
- Minting: 260K Gas
- Bids: 75K Gas
- Cancel Bid: 22K Gas
- Sale: 160K Gas
- Transfers: 95K Gas
As far as I can see, since Feb 2020 the average gas per transaction has always been around 60-70k (source) so that makes me wonder why some transactions take much more amount of gas (Minting, Sale).
My initial thought would be that NFTs could be sent and stored in the blockchain, similar to smart contracts but as far as I can see the content of NFTs is actually not stored in the blockchain (source).
- What are the factors involved in NFT gas consumption?
- What are good strategies to minify gas consumption? I can think of 2 important ones: deploy on a blockchain network which is not based on PoW / Proof of Work (we're likely to deploy on Matic/Polygon, which is based on PoS) + minify the amount of transactions. Any other suggestions?