“Low Head” for the purposes of this paper is considered to be where power is extracted cost effectively from a water level difference of between 1m and 3m. These conditions are widely found onshore and at numerous tidal locations along the World’s coastlines. Typical Significant Wave Heights also frequently fall within this range. Venturi-Enhanced Turbine Technology (“VETT”), the subject of this paper, was developed to economically exploit such low head renewable energy opportunities. Its development, logically, was started with small low-cost applications in onshore rivers. This initial phase of development is now advanced and commercial exploitation activity has commenced. Tidal VETT applications are under active development and the application of this technology to harnessing wave power is planned for the future VETT technology is a fluid step-up transformer formed by a passive venturi, through which most of the water flows to amplify the pressure drop across a turbine in the remainder of the flow. The cost savings and reduced environmental and societal impacts from using a simple, conventional, small, high-head, high-speed turbine-generator set in a low-cost passive duct is substantial when compared to the large, slow moving legacy technologies such as the waterwheel, Archimedes screw and tidal barrage type schemes. There are also a very large number of sites located worldwide for which this technology is well suited. Hence, VerdErg’s VETT low head renewable energy has much potential to offer.
