On the one hand, it is good to see development of energy sources that don’t require burning coal:

The world’s first deep-water device to generate electricity from the tides on a commercial scale is due to start operating within weeks.

A seagoing crane barge has lowered the 1,000-tonne double turbine into place and an operation to fix it to the seabed with 12 metre (40 ft) pins begins today.

On the other hand, one wonders if these turbines will be a threat to sea life in the same way that wind turbines are a threat to birds? The article doesn’t mention this aspect. Furthermore, this will be hard to monitor. Who, out in the middle of the ocean, will report the number of whales or tuna that get killed? Perhaps the turbines will spin slowly enough to not be a threat.