Renovation of Grid-Tied Solar Photovoltaic Plants: Problems and Prospects

Rapid development of energy technologies results, in particular, in that photovoltaic modules often become obsolete even before the end of their assigned service life. It is sufficient to say that, for the period from 2014 to nowadays, the average efficiency of photovoltaic modules has increased from 14–15 to 21%. The prices for photovoltaic products also continue to decrease. In this connection, the possibility of substituting the equipment of existing solar power plants with more advanced components is of interest. Photovoltaic module replacement versions, as well as technical and economic aspects of this process, are discussed taking Russia’s first grid-tied photovoltaic plant Kosh-Agach-1 as an example. The modern types of photovoltaic modules and the options of using them for solar plant renovation purposes are analyzed. The prime cost of the electricity generated is estimated with taking into account the replacements of modules and inverters. Special attention is paid to the compatibility of new modules with the old support structures and inverter equipment. The decrease of electricity prime cost after installing the new modules serves as the main renovation feasibility criterion. It is shown that the refurbishment of plants equipped with thin-film silicon modules by replacing them with domestically produced or Chinese modules consisting of silicon photovoltaic plates 166 × 166 mm in size looks to be the most promising option. The minimal prime cost of generated electricity is achieved in the case of using heterojunction modules and modules on the basis of photovoltaic converters with a rear contact.