“Circular bitcoin economies” are currently just an opportunity for forex arbitrage. As the input costs are one currency with the output value in another. Bitcoin miners must pay their electric bills in fiat.
A true circular bitcoin economy values energy inputs as bitcoin. As such, a metal miner or electricity provider, needs to evaluate their costs in bitcoin.
What are those actual costs? Todays world is just calculating an exchange rate. Where is the circular economy in that?
Can we not calculate the energy required to output a single block today, and assume that as input and 6.25+fees btc as the output, and calculate the energy required to perform tasks, and make assumptions about how much value individuals are providing in bitcoin terms?