In 20/20 hindsight, it appears to me that every major municipal sewage processing plant should have been designed with algaculture in mind. In that process, the toilet flushers would have been entitled to money for their plentiful daily product.

The nations of the world with fairly level deserts close enough to the ocean would seem to have an advantage. Is Africa potentially in this picture?

http://www.americanenergyindependence.com/biodiesel.html

"Consider if you will, a treaty between the United States and Mexico, where Mexico grants the U.S. a permanent right-of-way to the Gulf of California for the purpose of building a seawater canal that will transport a large and continuous flow of seawater from the Gulf of California into the USA. For the sake of discussion, let us assume that a canal has already been built between the Gulf of California and the Salton Sea; and that the Salton Sea will serve as a transfer reservoir. Visualize a large aqueduct between the Salton Sea and Death Valley where a second inland sea has formed, approximately the size of the Salton Sea. From these two inland seas, several aqueducts extend out into the deserts of the Southwestern United States; Reaching into Arizona, Nevada and New Mexico."

By Michael Briggs, University of New Hampshire, Physics Department