Heliostat aiming strategy of 3 cylindrical cavity-receivers integrated in a 750 kW solar tower hydrogen plant

摘要

Hydrosol is a series of projects with the main goal to produce Solar hydrogen by means of thermochemical cycles via water splitting. Hydrosol-Plant is the latest of these projects and is being installed at the CRS (Central Receiver System) solar tower facility of the Plataforma Solar de Almeria, with the main goal to develop and demonstrate the operation of a pilot plant in a 750 kW scale. This work presents the main features of the facility: The solar chemical reactor, consists of 3 cylindrical cavity-receivers containing a windowed aperture and a CPC (compound parabolic concentrator), and located in an equilateral triangle. These receivers are filled with a dome formed by bricks of redox material where the reactions take place. An optical-energy study is done and the total power supplied by the heliostat field is calculated for several representative time points of the year. Additionally, the power which is individually supplied by each heliostat has been also calculated, which is used to improve the control of the temperatures of the different steps of the thermochemical cycle. The main goal of these activities consists of giving accurate data to design an aiming point strategy which yields to a good distribution of concentrated solar flux onto the 3 modules within a limit for spillage. These studies also allowed to determine the final design of the three apertures of the receiver and their relative positions which permit to reach the required power to carry out the tests.