E. Muñoz-Cerón

Efficiencies and Energy Balance in High-Concentrator Photovoltaic Devices

Actual and forecast high-concentrator photovoltaic (HCPV) systems efficiencies may provide a scenario where HCPV represents a potential alternative to flat PV technology. The present status of HCPV efficiencies will be studied, and, on this basis, future trends regarding HCPV cells, modules, and systems efficiencies will be forecast. It will be shown that HCPV technology represents a real alternative to the current PV systems. Guidelines and normalized documents are needed to assess the overall performance of HCPV systems and to provide a general assessment of the potential of HCPV technology. The International Standard IEC 61724 publication, Photovoltaic System Performance Monitoring—Guidelines for Measurement Data Exchange and Analysis, will be highlighted. Because these guidelines are specially addressed to flat-PV technology, some suggestions, especially those adapted to the particularities of HCPV systems on both monitored and derived parameters, will be covered. Moreover, different indices of performance and losses that intend to provide comparisons between different HCPV installations will be offered adapted to the HCPV idiosyncrasy. These comparisons may be extremely useful when it comes to optimizing HCPV installation technology.

High-Concentrator Photovoltaic Systems Configuration and Inverters

A high-concentrator photovoltaic (HCPV) system is the result of the electrical interconnection of several CPV modules with additional components denominated “balance of system.” The wide variety of elements that compose a module makes possible different types of HCPV systems, although the most widespread is the point-focus pedestal type. Among the elements that compose an HCPV system, the inverter, which has been studied deeply for flat-PV systems, should be adapted to the particularities of HCPV technology. A different definition of weighted efficiency is proposed that has been adapted to an HCPV system located in southern Spain. This definition is compared with other ones proposed by some authors within this technology and also with the most used conventional PV systems definitions, which are the European and Californian efficiencies. It is highlighted that the differences are minimal. Beyond that, a novel classification of the most common interconnection configurations is proposed and some experiments were performed to show that the maximum power point tracker methods traditionally used for standard PV systems are somehow also valid for HCPV systems.