Initially, impact will be in paper citations, technical progress, and then community size. Later metrics will include: “Watt-Hours credited on network,” “Unique account addresses with nonzero balance (overestimate of unique users),” “Unique account addresses with activity in prior 168 hours,” “Funds directed to incentivizing renewable electricity,” and the harder-to-measure “Impact (esp. on sustainability) of decentralized applications secured by PREPchain.”