The concept of planning turbines on the beds of rivers, streams, and tidal basins seems to be an excellent addition to the mix of energy technologies that will eventually free the world from dependence on fossil fuels, which cause pollution and are often found in politically unstable parts of the world. Of course more research and development will be needed to establish the economic viability of the technology, as well as to allay the concerns of some groups about potential environmental impacts. If the technology is seen to be viable, then a time may come when the waterways of the world will become a source of clean, renewable, and unobtrusive energy.