Recycling

Recycling removes tao or alpha from issuance. The tokens return to the unissued supply and can be emitted again later.

Tao recycling

Recycled tao is subtracted from TotalIssuance.

• Root registration: the root registration cost is recycled directly, with no swap into alpha.
• Hotkey and coldkey swaps: the swap cost is recycled.
• Transaction fees: extrinsic fees are recycled, not paid to the block author. Fees paid in alpha are sold for tao from the subnet pool, and that tao is recycled. Any part of the fee that the transaction did not use is refunded to the payer in tao.
• Subnet dissolution: any tao left on the subnet account after stakers and the owner are paid out is recycled. This includes the tao share of protocol alpha and, for newer subnets, of the pool's alpha reserve. See Subnet Deregistration.

Subnet registration does not recycle anything. The whole lock cost seeds the new subnet's pool. See Subnet Registration.

Alpha recycling

Recycled alpha is subtracted from the subnet's alpha issuance (SubnetAlphaOut).

• Neuron registration: the registration fee is paid in tao and swapped through the subnet pool into alpha. The alpha bought with the burned share is recycled. The tao stays in the pool. On subnets with miner collateral, the collateral share is staked to the hotkey instead of being recycled.
• Subnet owner hotkey incentive: if the subnet's RecycleOrBurn setting is Recycle, miner emission to the owner hotkey is recycled. Otherwise it is burned.
• Root alpha that is not sold: when the sum of all subnets' moving alpha prices is at or below 1 tao, root's share of alpha dividends is not sold. It is recycled instead. Root's share is also recycled when no root validator on the subnet qualifies for it.
• Childkey burn: when a parent hotkey's emission passes to a childkey owned by a different coldkey, the network's childkey-burn proportion of that emission is recycled.
• recycle_alpha: any staker can recycle their own alpha with this extrinsic. This does not work on root.

Alpha bought by chain buys is not recycled. It is held as protocol alpha (SubnetProtocolAlpha). See Tao Emission.