Offshore hydroelectric plant: A techno-economic analysis of a renewable energy source

In a world where fossil fuel prices are subject to steep price hikes and where green house emissions are endangering the planet, dependence on non-renewable energy sources becomes more urgent. In this paper a technical feasibility and economic viability study of a new technology that utilizes hydroelectric power to tap the oceans׳ enormous energy reserve is presented. Called the Offshore Hydroelectric Plant, such an installation has an underwater powerhouse, the water from the turbines being discharged into a tail race sump (TRS). Power is generated when suitable head is created between the TRS and the sea, by leading the water out and allowing it to flow into giant troughs located in a vertical elevator building. Here, hoists raise the troughs carrying the excess water and empty them into an overhead tank (OHT). Water from the OHT is carried by penstocks to another powerhouse located at sea level. The plant utilizes the existing technologies of tidal plants, vertical ship lifts, and pumped storage schemes. Well-developed technologies of the offshore oil industry are utilized in fabricating the structures on shore, and towing them to location. An example demonstrates that a 104 MW plant could produce 569 GWh annually. Project investment costs are approximately $ 432 million and Levelized Electricity Costs $0.055/kWh.