A New Hybrid Ocean Thermal Energy Conversion-Offshore Solar Pond (OTEC-OSP) Design: A Cost Optimization Approach

Abstract Solar thermal electricity (STE) generation offers an excellent opportunity to supply electricity with a non-CO 2 emitting technology. However, present costs hamper widespread deployment and therefore research and development efforts are concentrated on accelerated cost reductions and efficiency improvements. Many focus on the latter, but in this paper we rather focus on attaining very low levelised electricity costs (LEC) by designing a system with very low material cost, while maintaining appreciable conversion efficiency and achieving low maintenance cost. All investigated designs were dimensioned at a 50 MW scale production. Calculated LECs show that a new proposed hybrid of ocean thermal energy conversion with an offshore solar pond (OTEC–OSP) may have the lowest LEC of 0.04 €/kWh. Addition of a floating offshore solar pond (OSP) to an OTEC system increases the temperature difference in the Rankine cycle, which leads to an improved efficiency of 12%, while typical OTEC efficiencies are 3%. This higher efficiency leads to much lower investments needed for power blocks, while the OSP is fabricated using very low-cost plastic foils. The new OTEC–OSP design can be located in many sunny coastal areas in the world.

[1]  W. Beckman,et al.  SOLAR ENGINEERING OF THERMAL PROCESSES Second Edition , 2009 .

[2]  W. Beckman,et al.  Solar Engineering of Thermal Processes , 1985 .

[3]  L. Vega.  Ocean thermal energy conversion primer , 2002 .

[4]  Arthouros Zervos,et al.  Energy sustainable communities, experiences, success factors and opportunities in the EU-25, EREC, European Renewable Energy Council , 2005 .

[5]  David R. Mills.  Solar energy options for renewable energy economies , 2000 .

[6]  Henry Kelly,et al.  Renewable energy : sources for fuels and electricity , 1993 .

[7]  I. Gorst.  Survey of energy resources , 1985 .

[8]  William S. Chandler,et al.  NASA Climatological Data for Renewable Energy Assessment , 2004 .

[9]  Andrew Swift,et al.  El Paso Solar Pond , 2001 .

[10]  F. Trieb.  Competitive solar thermal power stations until 2010—the challenge of market introduction , 2000 .

[11]  O. Bellwood,et al.  Recent advances in marine science and technology , 1995 .

[12]  K. Rafferty.  Geothermal Power Generation - A Primer on Low-Temperature, Small-Scale Applications , 2000 .

[13]  Thomas B Johansson,et al.  A Global Clean Cooking Fuel Initiative , 2004 .

[14]  Z. Şen.  Solar energy in progress and future research trends , 2004 .

[15]  Patrick K. Takahashi,et al.  Ocean thermal energy conversion: Its promise as a total resource system , 1992 .

[16]  Sathish Balasubramanian.  Renewable Ocean EnergyAn Overview of the State of the Art , 2002 .

[17]  Wim Turkenburg,et al.  Policies for renewable energy in the European Union and its member states: an overview , 2004 .