Solar Thermal Energy

Abstract

This chapter explains the origins of solar energy and explains the connection between the temperature of the sun and the radiation wavelength. Different systems for harnessing solar thermal energy, such as active and passive solar systems, as well as concentrated systems are discussed. Two case studies are presented.

Exercise 7

• 1. What are the differences between flat plate collectors and evacuated tube collectors? Which one do you think is better and why?

• 2. Find out the distinctions between line and point solar concentrators.

• 3. Do some research and gather ideas about the following: solar cooling, solar concentrators, Fresnel reflectors, parabolic dishes with solar Stirling Engines, pumped solar thermal system.

• 4. A parabolic trough of area 6 m² collects insolation of 1500 W/m² for 6 h. What is the total energy collected by the parabolic trough? [Answer: 195 MJ].

• 5. A solar thermal power plant has 50 MW capacity and produces 84 GWh of electricity/year. The plant is located in an area with consistent 300 sunny days/year. How many hours per year is the plant producing electricity? [Answer: 1680 h].

• 6. How much energy in MWh is produced per year from a flat plate collector of area 3.50 m × 3.50 m if the insolation for that location is 4.383 kWh/m²/day? The efficiency of the collector is 38%. [Answer: 7.45 MWh].

• 7. Discuss the concept of concentrated solar power (CSP).

• 8. Describe how the Mojave Solar Project in California has disrupted the habitat of natural species. What can be done to ameliorate the disruption caused to natural life? Could you think of any way to avoid this problem for any such large-scale projects in the future?