Why should water be the only source of power?

In a previous post,Mr.Muhigirwa has rightly pointed out that it is crucial to find ways to decouple water consumption and energy generation/usage. Taking his comment about biodegradable waste being used as an energy sourcefurther, here is an interesting article...


I invite comments from experts in the field. At what stages is water used in these processes? Could a place like Yemen which is slated to run out of water use such technology in a feasible manner?

( Sana'a risks becoming the first capital in the world to run out of viable water supply as Yemen's streams and natural aquifers run dry. More information@http://www.guardian.co.uk/global-development/2012/aug/27/solution-yemen-water-crisis)