Hydrokinetic Energy Conversion Systems and Utilization of River Current for Electricity Generation

Abstract

The growing demand for electrical energy is one of the most important challenges that the world is facing today. Hydrokinetics studies how kinetic energy is generated by the natural movement of water-river and streams currents and how to convert that energy to electricity. Hydrokinetic energy, the power of moving water, is a promising new, vast, and renewable resource of energy. To tap this source of hydropower, in-stream water current or kinetic energy turbines are deployed. These turbines generate power from the kinetic energy of a flowing stream of water without the use of a dam or barrage structures. Hydrokinetic devices are placed directly in the flow and generate energy only from the power of the moving water. Water current turbines can be installed in any flow with a velocity greater than 1.5 m/s. Because of low investment costs and maintenance fees, this technology is cost effective in comparison to other technologies. The continuous supply of electrical energy is also an advantage in comparison to solar power or other small-scale renewable technologies. This kind of small-scale hydropower is considered environmentally friendly, meaning that the water passing through the generator is directed back into the stream with relatively small impact on the surrounding ecology. Due to the low cost and durability of this kind of hydro-power systems, developing countries can manufacture and implement the technology to supply the needed electricity to small communities and villages. Systems can be installed in isolated or grid connected configurations, stand-alone or as a supplement to existing generators, floating or fixed to the bottom of a water course. Since many remote communities are situated near moving water these turbines represent a promising source of clean power. Kinetic energy turbines represent a significant yet untapped source of hydropower from South Africa’s and Botswana’s abundant water resources.  

This paper gives detailed information about current base of hydrokinetic energy for river application and power generation. Applications in free-flowing rivers and reviews of some of the existing turbine technologies are outlined. In addition to that, it has tried to give a future concept about suitable turbines for river currents and implementation challenges.