Simec Atlantis jumped 15% as its MeyGen tidal power generation site in the Moray Firth was awarded four Contracts for Difference (CfD) in the latest offshore auction round.
Under the contracts, MeyGen is guaranteed a price of £198 (£/MWh) for 15 years from the March 2028 commissioning date.
SAE added the CFDs will mean an additional 22Mw of electricity from MeyGen on top of the 28Mw allocated in the 2022 auction round.
In a statement, SAE said it had made good progress on the delivery of the 2022 award, noting that this new contract will help the project achieve greater economies of scale and mitigate cost increases.
MeyGen is already producing 6Mw a year but with this additional 50Mw will be able to power 65,000 homes annually.
SAE added it is in advance discussions with a consortium of global manufacturing and engineering firms for 3Mw turbines, which would be the most powerful tidal turbines ever deployed.
Shares rose 15% to 1.18p