Organic wastewater to energy

Photo source: Thames Water 

There is a quiet revolution going on in the water industry. The advent of carbon credits, feed in tarrifs and a sustainable approach is changing the economics and stimulating the rapid growth in energy from wastewater plants.

Two announcements this week highlight the change. Thames Water are now exporting biogas (methane) from its Didcot sewage works into the gas network.  While in Yorkshire an Archimedes screw and an ABB motor and variable speed drive operating as a generator is enabling electricity to be generated from the hydraulic head available.

Neither of these examples are using revolutionary technology – Archimedes screws date back to the Romans.  What has change is the mindset. Thinking holistically about the potential energy generation as well as the wastewater process is the key. It requires a multidisciplinary approach and thinking of wastewater as a resource, full of potential energy, bioenergy and biomaterial.