Selection of System Component and requirements for a hypothetical parabolic trough concentrated solar power plant in northern Nigeria

ABSTRACT The study proposed methods of determining the relative suitability of three major component/requirements of a hypothetical 100MW concentrated solar power plant in Malam-Fatori, a location in Borno State, northern Nigeria. The component/requirements to be selected are solar concentrators, heat transfer fluid (HTF) and thermal energy storage (TES) medium. The most suitable concentrator amongst three different variants; Sky Fuel Sky Trough 80-mm OD receiver (SF), Siemens SunField 6 (SSF) and EuroTrough ET150 (ET), was selected by subjecting them to simulation at varying solar multiples using the System Advisor Model (SAM). A comparative analysis of the simulated energy output, levelized cost of electricity (LCOE) and total solar aperture area was used to determine the most suitable concentrator. For HTF, the study compared the characteristics of Therminol VP-1 to that of Therminol 59, while for TES medium; HITEC Solar Salt, HITEC XL (Eutectic), HITEC XL (low calcium) and ordinary HITEC Salt were subjected to comparative analysis based on the climatic conditions of the location under review and the chemical composition of the various media. The study revealed that SF has highest annual energy output and the lowest LCOE, while also competing favourably in terms of land requirement (< 3% more land requirement than SSF and ET). It further revealed that Therminol VP-1 is preferable to Therminol 66 as HTF due to higher maximum operating temperature and maximum field flow velocity. Additionally, HITEC Solar Salt is the most preferred TES medium due to greater tolerance to high ambient temperatures and absence of corrosive calcium nitrates. Key Words: Concentrated solar power, solar multiple, parabolic trough concentrator, heat transfer fluid, thermal energy storage.