In Sierra Gorda, in the Chilean Atacama desert, where the highest level of solar radiation is on Earth, the Cerro Dominador solar complex is built, the first thermosolar plant in Latin America that will produce energy 24 hours a day. Sierra Gorda is a town that is about 1,400 kilometers north of Santiago and in the middle of Atacama, the absolute point of the driest desert in the world, where direct radiation is 3,500 kilowatts per hour, per square meter.
From the sky, Cerro Dominador looks like a spaceship, and on land, a wasteland with thousands of small towers with one that dominates over the rest, because in the 700 hectares will be installed 10,600 heliostats, that is, sets of mirrors, and one great tower of 250 meters. In the thermosolar plant, solar energy will be reflected by thousands of heliostats towards the top of a tower, where salts that are in a liquid state will be heated. The hot salts of the large tower will help generate steam, which, in contact with an electric generating turbine, will produce the final energy.
Fernando González, executive of Cerro Dominador, told Xinhua that this project is a combination of two plants, a photovoltaic of 100 megawatts (MW) and a solar concentration of 120 MW. This last plant, which has a storage capacity of 17.5 hours, will guarantee continuous production 24 hours a day, 365 days a year, being the first renewable energy plant that will produce base energy in Chile.
"The difference is that the photovoltaic converts the light rays into electricity, in the panel, and the thermosolar what it does is that it has mirrors that concentrate the light in a place to heat salt," González explained. Electric power will be injected into the National Electric System of Chile and will contribute 110 MW in 2020 when energy production begins.
González commented that this area in the north of Chile, at the absolute point of the desert, is one of the best places in the world for solar energy because there is no vegetation, animals, or people, so "work with this type of plants, the impact is zero, it's very favorable. " "This is the driest desert in the world, a very hard place, but I think that being part of this project, being part of the history, being part of the first thermosolar plant in Latin America, fills us all who work in that of pride, "he said.
For his part, the project's safety manager, Andrés Rodrigo, said that each heliostat weighs 1.8 tons and will concentrate the solar radiation to the solar receiver, located at the top of a tower 250 meters high. This concrete tower will be the second-highest construction in Chile, after the Costanera Center in Santiago, which measures 300 meters high, one of the highest skyscrapers in Latin America.
The violence with which ultraviolet rays impact this area of the planet forces workers to use the maximum security measures when installing heliostats, between 20 and 30 per day. The arrangement of the plant is concentric, with the large tower in the center surrounded by thousands of heliostats. The construction emulates the shape of plants such as sunflower, which maximizes the capture of light, without interference, thanks to its concentric distribution.
Rodrigo added that the difference that this plant has compared to other solar thermal power plants is that it has salt storage, which will allow energy to be produced at night. "It is a very important project for Chile, the first plant of this technology that is made in South America and the technology used is one of the most advanced," he said. This is the fourth plant of its kind in the world and will be added to those in the United States, Spain, and Morocco.