A research team from the Polytechnic University of Madrid has developed a new generation of more efficient photovoltaic components and with significant cost reduction, the main limitation of this clean energy.
A simple way to reduce costs of solar electricity is to make the converter, the solar cell, drive more light. The technology investigated by Ignacio Rey-Stolle, Professor, Department of Physical Electronics of the Technical School of Telecommunication Engineering of the Polytechnic University of Madrid, combining extremely pure semiconductor materials and complex, they get high conversion efficiencies, with optical elements focus the beam on a reduced size converter. This has reached the multijunction solar cell production with yields near 40%, operating at a light intensity equivalent to 200 suns.
Solar photovoltaic energy is an alternative to fossil fuel consumption, causing the so-called climate change through emissions of greenhouse gases. This renewable energy has several advantages associated with its robustness, modularity, ease of application and wide and regular distribution of solar radiation, its resource base.
However, despite its great attraction, solar energy is now a very small percentage of power generation capacity due to their price, which is determined by the cost of the solar cell. The studies of Professor Rey-Stolle, a researcher at the Group III-V Semiconductors Institute of Solar-UPM, decrease the price of this technology to reduce the cost of its basic devices.
Improved high-concentration photovoltaic systems
The scientific activity of Rey-Stolle, who was recently recognized with one of the prizes that the General Foundation of the PSUs awarded to the Technological Research and Development of teachers under thirty-five years, focuses on solar photovoltaics, converters specifically photovoltaic or solar cells made of semiconductor III-V family. The ultimate goal of research is the fabrication of devices with efficiencies of around 35% when illuminated with light equivalent to 1000 suns, features that would ensure the achievement of the objectives of EU costs for electricity from PV.
In this research, Semiconductor Group III-V of the IES-UPM pursued obtaining the viability of solar energy, works since 2002 the only existing commercial MOVPE reactor in Spain and one of the few in Europe related to photovoltaic research. With the MOVPE reactor, located in the laboratory of Solar Energy Institute and listed as a “great scientific equipment” of the PSUs have been able to produce structures that have reached efficiencies of 26.2% at 1000 suns unijunction cells (world record efficiency for these cells) and 28% in multijunction cells, which is expected in the short term exceed 30% efficiency.
Professor Ignacio Rey-Stolle, Telecommunication Engineering from the Polytechnic University of Madrid, completed his graduate studies at the Institute of Solar Energy, and since 2003 is Professor in the Department of Physical Electronics School of Engineering Telecom-UPM.
