Answer to Question 1
There is an aphorism that you can't do just one thing. This is true for tidal
energy projects as well. There may be many environmental drawbacks that have not yet been
recognized, but there are certainly known drawbacks. The underwater blades will certainly
collide with fish and this would have a direct effect. There are also indirect effects that are
caused by the churning action of the blades..
Discussion Questions
Answer to Question 2
The ocean floor is the main supply of concentrated manganese, but deposits exist
on land and these supply the bulk of the manganese used worldwide.
