4.0 Introduction

We’re trying to figure out how big the problem is and what we can do to minimize bird mortalities.

— Eric Davis, Feb 2014. (Assistant regional director for migratory birds at the US Fish & Wildlife Service’s Sacramento office, commenting on bird deaths at the Ivanpah concentrating solar power plant.)

Solar concentration is the most cost effective way to achieve sufficiently high temperatures for generating steam for useful work. Concentration of solar radiation is acheieved by using an optical device between the source and absorber, and that allows to decrease the effective area of the absorber and associated radiative energy losses.  As such, concentrating collectors are advantageous when high temperatures are needed. The one remaining caveat is that concentrating technologies typically rely on the direct normal irradiance component of the solar resources. Hence, locations with regularly clear skies and high levels of direct radiation (such as the southwest US and southern Spain) are best suited for concentrating solar power.

Learning Objectives

• Recognize various configurations of solar concentrators
• Calculate concentration ratios for concentrating collectors
• Analyze the optical characteristics of non-imaging optics.
• Compare thermal performance of concentrating systems.

What is due for Lesson 4?

This lesson will take us one week to complete. The list of assignments for this lesson is provided in the table below. More detailed instructions are given on respective pages of this lesson and in Canvas modules.

Questions?

If you have any questions, please post them to our Questions and Answers discussion forum in Canvas. I will check that discussion forum daily to respond. While you are there, feel free to post your own responses if you, too, are able to help out a classmate.