Nowadays a 1.72-MWp PV plant is nothing out of the ordinary. Nevertheless, if we pay attention to innovation, research and development, the ‘La Silla’ solar plant, promoted by Enel Green Power and installed and designed by Soltec, a leading manufacturer of single-axis trackers,turns out to be an outstanding project.
This plant is located in the outskirts of Atacama Desert, in the Region of Coquimbo (Chile), at 5,900 feet (1,800 meters) altitude. It is very close to the European Southern Observatory, which will receive this renewable energy. This location is not unintentional. Since this is an experimental plant, the high radiation and clear sky characteristics of the site make for an excellent PV technology test bed.
This solar plant is unique, and not only because of powering an astronomical observatory. It also contributes to the development of the solar industry at a fundamental level. The plant counts on three different types of modules for efficiency and productivity analysis. Soltec specifically designed and developed for them two solar trackers: SF Utility SP4x19L-72 and SF Utility SP2x44P-60bi. These trackers increase yield generation for the three types of modules that are: bifacial, conventional polycrystalline, and smart polycrystalline that increases production at certain conditions.
As a result of the participation in this project, Soltec developed the first solar trackers mounting bifacial modules at a utility-scale. This tracker model maximizes yield production thanks to the exploitation of the sun light reflected on the ground. Bifacial modules are able to harvest diffuse reflectivity boosting its theoretical yield production up to 30 percent. For conventional and smart modules, Soltec designed and installed a landscape configuration tracker with 4 rows of 19 modules each.
The standard design of SF Utility provides the greatest tolerance of application variables on the market including steep-slopes to 17 percent grade North-South and greatly reduced civil works including land grading and pile driving. Moreover, the standard SF Utility configuration results in wider aisles between rows facilitating operations and especially unobstructed maintenance access.
At La Silla Soltec has rolled-out a latest cost reducing innovation in the form of the PV Cabling Harness that is pre-fabricated and installs within the tracker torque-tube and so reducing material and labor costs associated with cable trays and conduit and their installation. Wires remain protected from environmental conditions and the electrical installation gets simpler.
Another remarkable innovation of this plant is the application of SF Utility Self-Powered that imposes zero impact on available array active-area, and minimizes operational power expenses over the life of the project. Self-Powered avoids grid-powered installation first costs, and avoids market-rate power billing for the life of the power plant. The principal component of innovation is Soltec’s patented PV Series Power Supply that integrates with an active-area PV series-string resulting in high Self-Powered system availability and with no occupation of otherwise revenue generating PV active-area. Moreover, with the electricity selling price being the lowest electricity price on site, Self-Powered will supply the lowest price electricity on site, and independently at each tracker.
According to Project Engineer Eduardo de San Nicolás, “La Silla presented several technical challenges while incorporating cutting-edge technologies of tracking, generation, transformation and monitoring while still maintaining cost effectiveness in land use, civil works and rapid deployment. Thanks to our great engineers and investment in R&D, we had the chance of taking part in one of the most significant solar plants across the globe.”
Further operational innovation was rolled-out in the form of tracker integrated string-boxes that f
“Soltec is a high tech company, we have developed from micro inverters to CPV PV modules. We are passionate about technological challenges and we enjoy providing solutions of all kinds. The Sf Utility single-axis trackers, installed in the ‘La Silla’, for bifacial modules are proof of that,” says Raúl Morales, CEO of Soltec.
Experimental plant
Implementation of new technologies and development finds its cause in the plant’s research nature. Enel Green Power, developer of the project, decided to use this plant as a test bed of different PV technologies under real conditions for the investigation of increasing PV yield performance.
“The ‘La Silla’ has been a project full of exciting challenges from the technical point of view. The innovation and commitment to renewable energy is a hallmark for Enel Green Power and with the help of proactive companies like Soltec we are confident to overcome any challenge,” ensure Juan Francisco Mateo, Project Engineer in the ‘La Silla’.
Chilean Ministry of Energy Máximo Pacheco valued the experimental nature of ‘La Silla’ during its inauguration: “Chile has a tremendous potential for solar energy due to the radiation we have, among the highest in the world. What we see in this project is a complement of that, because we are not only able to produce electricity, but also move forward in technological innovation. We have the opportunity to make Chile become a laboratory for solar power and this is what we are witnessing.”