Suggesstion: Proof of stake

I am very new to crypto, but as far as I understand, proof of stake is better in environmental terms, because of a much smaller energy consumption. Would it be possible to change the proof of work of BGL to proof of stake or would it be easier to add the expiration mechanism to an already existing coin using proof of stake?

The issue names no files, tests, or entry points. Start by locating the existing proof-of-work consensus implementation and documenting the project’s consensus architecture; clarify whether replacing it or integrating proof of stake is intended, then define validation criteria for the chosen design.

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