Modelling and Analysis of a CSP Plant Technology for Small Power Networks -Technical and Financial Evaluation Innocent E. Davidson HVDC/Smart Grid Research Centre School of Engineering, University of KwaZulu-Natal Durban, South Africa E-mail: Davidson@ukzn.ac.za Nicky K. Mbaimbai Electrical Engineering Department Burmeister & Partners Consulting Engineers Windhoek, Namibia E-mail: nicky@burmeister.co.na Abstract—Namibia, like several Southern African Development Community (SADC) member states, is projected to experience power shortages in the near future due in part to the expiration of power purchase agreements and contracts. Various solution options are being considered to alleviate this deficit and to diversify Namibia’s energy mix. Concentrated solar power plant (CSP) is a solution option under consideration. Using RETScreen the Excel-based clean energy project analysis software, as a decision-support tool, models of CSP installations of varying capacities were developed. A technical and economic evaluation of the CSP as a viable solution option was carried out. Results of emissions analysis of the effect of the CSP installation on the environment in terms of greenhouse gas (GHG) emissions are presented. A comparison of the unit cost of electricity from CSP and conventional forms of electricity generation schemes (coal, wind and nuclear power) was carried out. CSP has the highest unit cost of electricity and the most environmentally friendly option. It becomes cost-competitive with some subsidies on the capital investment. Keywords-RETScreen CSP, renewable energy, SADC I. INTRODUCTION Concentrated solar power (CSP) is a renewable energy technology that is used in the generation of electrical energy by using the sun as a source of energy. CSP is a method of electricity generation that uses optical elements (mirrors) to focus sunlight onto a heat transfer medium [1].The high pressure, high temperature steam that is produced from the heat transfer medium is then used to rotate a turbine that in turn rotates a generator resulting in the generation of electricity. The sun is a non-depletable source and thus CSP is a renewable and clean method of energy generation. Molten-salt storage is already commercially available for concentrating solar power (CSP) plants, allowing solar power to be produced on demand and to “backup” intermittent renewable sources such as wind and photovoltaics [2]. Near- term advances in molten-salt power tower technology include planned up-scaling, improvements to the thermal properties of molten salts and the development of storage solutions in a single tank. These developments make CSP an attractive option to provide dispatchable solar power with capacity to provide energy storage for 100% renewable electricity grids [2]. The Southern African Development Community (SADC) faces critical energy shortages as the region’s electrical infrastructure significantly lags behind the region’s projected economic growth [3, 4]. Namibia like other SADC countries faces impending electricity shortages and power deficits that are expected to have grown to approximately 350 MW by the year 2015 [5]. Due to the inability of the current installed infrastructure to meet the electricity demand, the construction of a concentrated solar power plant (CSP) has been proposed to meet the projected demand as well as improve on the security of supply [6, 7]. A case-study has therefore been initiated to ascertain the economic and technical feasibility of setting up a CSP plant in Namibia. The results of this study could then be extrapolated to the entire SADC region with similar environmental conditions. II. CSP TECHNOLOGIES CSP plants are mostly implemented using four systems, namely: linear fresnel reflectors (LFR), parabolic troughs, stirling dishes and power towers. A. Linear Fresnel Reflectors (LFR) This technology is currently under development and is similar to that used in parabolic trough systems. The system consists of strips of mirror that are positioned as to direct the solar radiation onto central receiver tubes. This process which is called fresnelization is used to heat water in the receiver tubes thus producing steam which is used for electric generation as in parabolic trough systems. This system is considered to be less efficient than the other technologies as heat storage is not yet possible [8]. B. Parabolic Troughs The parabolic trough technology uses large parabolic reflectors to concentrate sunlight onto evacuated tubes that are filled with a heat transfer fluid (HTF).The heat transfer fluid (HTF) is then heated to very high temperatures. The HTF is then pumped to a heat exchanger where the heat is transferred to water thus producing steam. The super-heated This project is supported by Eskom Centre of Excellence in HVDC Engineering, University of KwaZulu-Natal, the Faculty of Engineering Research Centre (FERC), University of Namibia and Eskom TESP).