More digression on tidal power.
Siemans, the giant German company, is conducting research into tidal generation.
The plant off the Irish coast (Marine Current Turbines Ltd) should be mentioned. It is small, 1.2 megawatts, but the work is promising.

Hydrovision Brasil will conduct a conference this coming September:
http://www.hydrovisionbrasil.com/en/request-for-information; to get on their mailing list.