Summary and Activities
Lesson 2 covers fundamental principles of light concentration that are important for a number of solar energy conversion technologies - both thermal and photovoltaic conversion. The general scheme of the solar energy concentration is this:
Input solar energy flux ⇒ Optical concentration device ⇒ Output concentrated solar energy flux
We touched upon each of these stages. First, we looked at the available solar radiation at the earth surface - the input we start with. Then, we considered a few techniques that concentrate the available flux, confining it to a smaller area. Finally, we looked at the output and its characteristics. Theoretical and empirical laws presented in the readings provide you with the background for estimating such parameters as concentration ratio and output energy density. Most of the theoretical considerations presented here are made for ideal systems. In reality, you can expect that imperfect optics will require additional corrections for non-ideality and losses. Limitations and advantages of specific concentrating technologies will be considered in further lessons, separately for CSP and photovoltaic systems.
After you have covered the assigned materials for this lesson, please complete the following assignments:
|Reading Quiz||Please complete the Lesson 2 Reading Quiz.|
|Written Assignment|| Lesson 2 Activity: Light Concentration Problem Set
References for Lesson 2
Stine, W.B. and Harrigan, R.W., Solar Energy Systems Design, John Wiley and Sons, Inc., 1986.
Duffie, J.A. and Beckman, W.A., Solar Engineering of Thermal Processes, 4th Ed., John Wiley and Sons, 2013.
Mendelsohn, M., Lowder, T., and Canavan, B., Utility-Scale Concentrating Solar Power and Photovoltaics Projects: A Technology and Market Overview 2012, Technical Report
NREL/TP-6A20-51137, April 2012
Baig, M.N., Asad, K.D., and Tariq, A., CPC-Trough—Compound Parabolic Collector for Cost-Efficient Low-Temperature Applications, Proceedings of ISES World Congress 2007 (Vol. I – Vol. V) pp. 603-607 (2009).
Evans, D.L., On the performance of cylindrical parabolic solar concentrators with flat absorbers, Solar Energy, 19, 279 (1977).
IPS - Radio and Space Services, Australian Government (accessed Oct. 2014).
Hottel, H.C., A Simple Model for Estimating the Transmittance of Direct Solar Radiation Through Clear Atmospheres, Solar Energy, 18, 129 (1976).