Amount of ALGO required to meaningfully participate in consensus

How many ALGO are currently online, participating in consensus? And by extension, how much ALGO would be required to participate in consensus, at a meaningful rate (e.g. 1-2x/day, at an average of 500,000tx/day)?

You can check live data on ALGO participating in PPoS on Algorand Metrics Decentralization Dashboard or on AlgoExplorer.

I’m not sure I understood the second part of you question but, in my view, each and every ALGO placed at the service of the PPoS and kept properly online through your node is a meaningful decentralization act.

Between 6,000 and 11,000 algos more or less.