The UK's longest river, the Severn, is open for private tidal power projects, the government said.
The government recently rejected a Severn power project that could have supplied as much as five percent of the nation's power.
The government had been examining five options for tidal projects on the river, which it says has a 14-meter (46-foot) tidal range, one of the biggest in the world.
Three of the proposals were for barrages spanning the river, and two were tidal lagoons.
The Severn runs 220 miles from central Wales to the sea between Wales and southwest England.
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