Exergetic analysis and performance evaluation of parabolic trough concentrating solar thermal power plant (PTCSTPP) V. Siva Reddy a, * , S.C. Kaushik a , S.K. Tyagi b a Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India b Sardar Swaran Singh National Institute of Renewable Energy, Jalandhar-Kapurthala Road, Wadala Kalan, Kapurthala 144601 (Punjab), India article info Article history: Received 9 July 2011 Received in revised form 16 December 2011 Accepted 14 January 2012 Available online 17 February 2012 Keywords: Parabolic trough Thermal power Exegetic analysis Energetic analysis PTCSTPP STPP abstract Energetic and exergetic analysis has been carried out for the components of the solar thermal power plant system (parabolic trough collector/receiver and Rankine heat engine). The energetic and exergetic losses as well as efficiencies for typical parabolic trough concentrating solar thermal power plant (PTCSTPP) under the specific operating conditions have been evaluated. Operating pressures for a Rankine heat engine have been optimized for maximum efficiency. It has been found that, the energetic and exergetic efficiencies of PTCSTPP increased by 1.49% and 1.51% with increasing pressure from 90 to 105 bar respectively. Progression of the STPP from the variable load to full load conditions, the year round average energetic efficiency can be increased from 22.01% to 22.62% for the location of Jodhpur, and in case of Delhi, it can be increased from 20.98% to 21.50%. Year round average exergetic efficiency can be increased, from 23.66% to 24.32% for the location of Jodhpur and in case of Delhi, it can be increased from 22.56% to 23.11%. Land areas required for the 50 MWe thermal power plants are 79.2 ha and 118.8 ha respectively for the locations of Jodhpur and Delhi. Ó 2012 Elsevier Ltd. All rights reserved. 1. Introduction India is the major consumers of electricity due to the rapid economic growth and large population. A massive increase in base load electric power generation by conventional coal fired plants would lead to greenhouse gas emissions. Development of solar energy power generation technologies on a large scale is required for controlling environmental problems. Then coal can also play a comparably major and long-term role for future. So far, 921 MW of concentrated Solar Power (CSP) plants has been installed world- wide and Parabolic Trough Concentrators contributing 93% of total installed capacity. It required direct normal solar radiation and it is the major drawback of it. A heat storage reservoir must be inte- grated into the oil circuit as suggested by Vogel and Henry [1] to access its power around the clock. Numbers of design and performance evaluation methods of PTCSTPP are available in literature. Few of them are discussed here. Wittmann et al. [2] proposed a methodology to set up an economically optimized bidding strategy at the energy exchange. Quaschning et al. [3] proposed a new method for estimating the optimized solar field size as a function of the solar irradiance. Birnbaum et al. [4] suggested an additional thermal inertia to stabilize the steam temperature for a safe turbine operation. Gaul and Rabl [5] investigated the incidence-angle modifier for parabolic troughs to clarify the connection between collector tests and prediction of long-term energy delivery by a collector array. The exergetic performance analysis not only determines the magnitudes, location and causes of irreversibilities in the plants, but also provides more significant assessment of the individual components efficiency of plant [6]. Siva Reddy et al. [7] presented component wise energy and exergy analysis review of different thermal power plants. Kaushik et al. [8] has presented second law analysis based on the exergy concept for a solar thermal power system. Relevant energy flow and exergy flow diagrams are drawn to show the various thermodynamic and thermal losses. It was reported that the main energy loss takes place at the condenser of the heat engine part whereas the maximum exergy loss takes place in the collector-receiver assembly. Gupta and Kaushik [9] carried out the energy and exergy anal- ysis for the different components of a proposed conceptual direct steam generation solar trough power plant. It was found that the maximum energy loss takes place in the condenser followed by the solar collector field (including the trough concentrators and absorbers), while the maximum exergy loss occurs in the solar collector field. Palenzuela et al. [10] presented a thermodynamic evaluation of different configurations for coupling parabolic-trough * Corresponding author. Tel.: þ91 9891742963. E-mail address: vundelaap@gmail.com (V.S. Reddy). Contents lists available at SciVerse ScienceDirect Energy journal homepage: www.elsevier.com/locate/energy 0360-5442/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved. doi:10.1016/j.energy.2012.01.023 Energy 39 (2012) 258e273