Current concentrating solar radiation technologies for environmental generation of steam, power and hydrogen

Abstract

Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.This paper assesses current solar radiation concentrating systems for the purpose of industrial scale steam, power, and hydrogen generation with no or reduced amount greenhouse gas emissions. Solar power concentrating energy systems for the purpose of steam and power generation are presented along with brief information on advantages and disadvantages of these systems. Then the industrial scale applications of these systems are given to highlight the already commercial use of these systems as an alternative to coal or natural gas power plants. Solar power plants that are under construction are also summarized to point out the world wide ongoing investments in this field. Although there are no large scale hydrogen generation plants yet, the paper points out that the existing steam and power generation systems via concentrated solar energy can make use of already established infrastructure for hydrogen generation by replacing the receiver with a proper unit, such as a solar reactor. Then the paper provides an example solar concentrating system of a laboratory scale specifically constructed to generate hydrogen in a solar reactor. Based on this example, integration of that system into an existing solar concentrating power plant system is discussed. The paper concludes with examples of some of the industrial scale solar driven applications established in various countries as illustrative examples to underline the expectation for seeing similar commercial solar driven systems for the purpose of hydrogen generation as well.