Seafood is popular on many menus, but over-fishing is costing the oceans dearly. Aquaculture is one answer, with fish farmed for consumption in protected environments. In South Africa, the industry is in its infancy, but companies are farming fish that are green-listed on the Southern African Sustainable Seafood Initiative.
It looks like something from a sci-fi film, with its massive tower and thousands of wall-like solar mirrors set in an arid and deserted landscape. But Khi Solar One, Africa's first concentrated solar power project, is a very real example of the future of renewable energy.