A crash course in changing the world.
If you look at the map(thanks Los Alamos National Lab) there are clear areas with strong currents that could be use to harness energy using the Tides.
from my point of view, please correct me if i am wrong, in the same way we have lighthouses on the top of cliffs. we could use this areas close to cliffs that do not have heavy boat or ships traffic to put Tidal Power Plants(Tidal Turbines, Thermal conversion in areas closer to Antarctica, and Wave Energy).
The southern tip of South America and South Africa, could be ideal places for this type of technology.
According to the map above I think we could implement Tidal turbines all along the East Coast of Africa and produce enough energy for most of the countries in the south, collaborating together to distribute it efficiently.
just a thought :)