Heat Transfer in Power Generation

Chapter 7

Abstract

demand hours.

1. Introduction

119

Transfer

Fadi Alnaimat and Yasir Rashid

Advances in Concentrated Solar

Solar energy has the potential to reduce the dependence on the dwindling supply

of fossil fuels through concentrated solar power (CSP) technology. CSP plants utilize solar thermal energy to produce electrical energy based on different thermodynamic power cycles. Solar collectors, reflectors, receivers, thermal fluid, and turbines are the main components of each CSP plant and involve intensive heat transfer at all stages. This chapter illustrates the thermal characteristics of the main components used in CSP technology. In addition, the solar thermal fluid characteristics and its stable operational ranges are discussed in this chapter. Heat capacity, vapor pressure, volume expansion, density and viscosity of the thermal fluid should not differ significantly at different temperatures during various operation stages because these variations can cause failure in the system, which is designed at the fixed material properties. Currently, CSP technology is associated with a higher cost compared to the electricity generated through gas power plants. Many efforts are made to search for sustainable and inexpensive materials to minimize the cost of CSP. One critical issue faced by CSP technology is the intermittent nature of the sun. Modern CSP plants integrate thermal energy storage (TES) unit to smoothen the power production or to shift the production from peak sunshine hours to peak

Keywords: concentrated solar power, thermal energy storage, sensible and latent

Solar energy is the most abundantly available source of energy theoretically. It can be used to produce electricity by thermodynamic process and by photovoltaics conversion [1]. Initially, photovoltaic technology was incepted to convert solar energy into electricity. In this technology, solar cells produce electricity when exposed to irradiance. The amount of voltage produced per unit cell is very small; hence, hundreds of such cells are connected in series and parallel junctions to finally produce high voltage for daily use applications. Such systems are called PV arrays which are available from domestic scale to grid-connected commercial plants. In some cases, solar irradiance is concentrated at a small PV surface to generate more electricity from small PV surface; however, such systems have certain implications like accelerated thermal degradation [2]. Such systems are called concentrated

heat storage materials, thermochemical materials

Power: A Perspective of Heat
