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a systemic approach to energy

Editor-in-Chief: Schlögl, Robert

Managing Editor: Tiedtke, Marion

Editorial Board: Luther, Joachim / Meng, Qingbo / Hüttl, Reinhard F. / Koumoto, Kunihito / Gasteiger, Hubert

SCImago Journal Rank (SJR) 2018: 0.248
Source Normalized Impact per Paper (SNIP) 2018: 0.421

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A Generalized Approach for Enhanced Solar Energy Harvesting Using Stochastic Estimation of Optimum Tilt Angles: A Case Study of Bangkok City

Sachin Muralee Krishna / Nimal Madhu M / Vivek Mohan / Reshma Suresh M P / Jai Govind Singh
Published Online: 2015-12-23 | DOI: https://doi.org/10.1515/green-2015-0015


This paper estimates the monthly, seasonal and yearly optimal tilt angles that maximize solar irradiation received on an inclined surface, thus enhancing the energy harvested. The uncertainties in global and diffuse radiations on the horizontal surface are accounted using stochastic analysis of their daily statistical measured data. The measured data is taken over a seven-year time span. The study is carried out for south-facing flat plate solar collectors at the Bangkok site, Thailand, situated in the northern hemisphere. The position of the sun at any time and location is predicted by the mathematical procedure of Julian dating. Further, four isotropic and anisotropic sky models are used to evaluate the ratio of diffuse solar radiation on an inclined surface to that on a horizontal surface. The best sky model is opted by using the ranking method of errors and is used for further analysis. Moreover, the frequency distributions of global and diffuse radiations are studied using four types of probability density functions (PDFs), viz., Weibull, lognormal, gamma and beta. Kolmogorov–Smirnov (K-S) test is used as a criterion to find the best fit among the aforementioned PDFs. The proposed optimization problem is solved using particle swarm optimization with time-varying acceleration coefficients (PSO-TVAC). The monthly tilt angles obtained are found to be varying with respect to the corresponding latitude angle, suggested by the thumb rule. The collected energy using this tilt angle over a period of one year is found to be 588MJ/m2 in excess to that harvested using the latitude angle.

Keywords: tilt angle; diffused radiation models; particle swarm optimization (PSO); error analysis; probabilistic uncertainty; solar energy harvesting


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About the article

Sachin Muralee Krishna

Mr. Sachin Muraleekrishna was born in Kerala, India, in 1992. He completed his B.Tech degree in Mechanical Production Engineering from the National Institute of Technology Calicut, India. He is currently pursuing Master of Engineering at Energy FoS, Asian Institute of Technology, Thailand. He is working on biofuels and renewable energy.

Nimal Madhu M

Mr. Nimal Madhu M was born in Kerala, India, in 1987. He received a B.Tech degree in Electrical and Electronics Engineering from Calicut University, India, and an M.Tech in power systems from Indian Institute of Technology Bombay, India. He is currently pursuing doctoral degree in Engineering at Energy FoS, Asian Institute of Technology, Thailand.

Vivek Mohan

Mr. Vivek Mohan was born in Kerala, India, in 1986. He received a B.Tech degree in Electrical and Electronics Engineering from Amrita University, India, and an M.Tech in power systems from University of Calicut, Kerala, India. He is currently pursuing doctoral degree in Engineering at Energy FoS, Asian Institute of Technology, Thailand. He is working on stochastic optimal energy, reserve and risk management in microgrids.

Reshma Suresh M P

Mrs. Reshma Suresh M P was born in Kerala, India, in 1987. She received a B.Tech degree in Electrical and Electronics Engineering from Amrita University, India, and an M.Tech in power systems from University of Calicut, Kerala, India. She was Assistant Professor at Amrita School of Engineering and IES College of Engineering in Kerala, India. She is currently working as consultant for IEEE PES-ISGT conference in Energy FoS, Asian Institute of Technology, Thailand.

Jai Govind Singh

Dr. Jai Govind Singh received his M.Tech from IIT Roorkee and PhD from IIT Kanpur, India. He is currently working as assistant professor in Asian Institute of Technology, specialized in power system stability, FACTS, deregulation and smart grid and microgrid. He was a post-doctoral researcher at the University of Queensland, Brisbane, Australia, and Royal Institute of Technology, KTH, Sweden.

Received: 2015-09-20

Accepted: 2015-12-07

Published Online: 2015-12-23

Published in Print: 2015-12-01

Citation Information: Green, Volume 5, Issue 1-6, Pages 95–107, ISSN (Online) 1869-8778, ISSN (Print) 1869-876X, DOI: https://doi.org/10.1515/green-2015-0015.

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