Can stamp duty be paid based on actual power supply?

Stamp tax is levied on power purchase and sale contracts signed between power plants and power grids, and between power grids and power grids (except for the mutual power supply between power grids at all levels within the State Grid Corporation system and China Southern Power Grid Corporation system).

The power supply contract signed between the power grid and the user is not a voucher for enumerated stamp tax, and no stamp tax is levied.