Posted tagged ‘Institute of Solar Energy’

Dual-Junction Solar Cell Sets World Efficiency Record at 32.6 Percent at 1000 suns

November 18, 2008

Via: Semiconductor Today

The III-V Semiconductors group of the Instituto de Energía Solar at Universidad Politécnica de Madrid (IES-UPM) in Spain has set a new record for solar energy conversion efficiency of 32.6% for a dual-junction photovoltaic cell.

Designed and fabricated in a horizontal MOCVD reactor by IES-UPM’s III-V Semiconductors group, the lattice-matched dual-junction solar cell was independently measured at the calibration laboratory of the Fraunhofer Institute for Solar Energy Systems (FhG-ISE) in Freiburg, Germany. The 32.6% efficiency was measured under light concentration of 1026 suns (where one sun is the amount of light that typically hits the Earth on a sunny day), while at 2873 suns the efficiency is still 31.1%. 

Professor Carlos Algora, director of the group, says that the new cell is an important advance for terrestrial concentrated photovoltaic (CPV) modules, which use lenses or mirrors to focus sunlight onto the solar cells. 

Courtesy of Madri+dIES-UPM says that its new solar cell differs significantly from the previous record holder, made by Fraunhofer ISE (which, in 2000, achieved 31% at 300 suns). It adds that the importance of the new record is not only the efficiency increase of 1.6%, but also the concentration level (1026 suns versus 300 suns). As a rule of thumb, the higher the concentration, the lower the resulting price of the generated electricity. IES-UPM reckons that, after about five years of development, the cost of solar electricity from CPV systems based on this type of solar cell would be about 5.5c€/kWh, while at present the cost of electricity in Spain (generated by all available sources: nuclear, oil, coil, gas, renewable etc) is about 7.5c€/kWh.

Algora stresses that this record dual-junction solar cell represents a step towards improving the efficiency of triple-junction solar cells, for which the efficiency record of 40.8% was achieved under concentration of 300 suns by the US National Renewable Energy Laboratory (NREL). Researchers in the IES-UPM’s III-V Semiconductors group think that integration of its dual-junction structure into a triple-junction solar cell could result in a device with efficiencies of more than 41% at 1000-sun concentration.


Taming the wind and sun

May 19, 2007


Molinos de viento Windmills in La Mancha (Both the old and new varieties)

Originally uploaded by Zilargile (Top) and Strawjam (Bottom)

Everyone that has heard about La Mancha, knows from the musical and the Quixote novel that it is a sun-drenched land of windmills that might be giants (or not).

With all that sun and wind, the thinking of the locals seems to have been”If we got them, let´s put them to good use! ”

Correspondingly, the landscape in the region is dotted here and there with the iconic modern version of the windmills, that make a stellar appearance in the movie “Volver” by Almodovar.

Trying to profit from the other natural resource in abundance in the area, regional authorities are pushing forward an ambitious plan to boost solar energy. Besides the plants mentioned in my previous posts in Puertollano (solar thermal power), the city is the site for the Institute of Concentration Photovoltaic Systems or ISFOC (website in Spanish only).

The Institute launched a RFP for the development of plants using Concentrator Photovoltaic (CPV) technologies for a total capacity of 2.7 MW. The companies selected to build the plants are:

logo-foton.gif Guascor Foton (Spain/US, 300 KW)

images1.jpg Concentrix (Germany, 500 KW)

images2.jpg SolFocus (US, 500 KW)

isofoton.jpg Isofoton (Spain, 700 KW)

These commercial plants are going to be grid-connected and sited in different provinces of the region of Castile-La Mancha. The headquarters of ISFOC will house demonstration plants (200 KW) for each of the technologies employed in the commercial plants.

Concentrator Photovoltaic systems are experiencing a very interesting moment worldwide, with record gains in efficiency by Spectrolab (Boeing) and many companies taking their products to market. Spectrolab has an agreement with Solar Systems (Australia) to provide it with 500,000 concentrator solar cell assemblies to be used in remote rural communities.

Guascor Foton is one of the pioneers in Europe in this technology, the development of which stems from a partnership with the American company Amonix. Guascor Foton installed the first commercial high concentration CPV plant in Europe at the campus of the upm.jpgPolytechnic University of Madrid. This project was developed in collaboration with the Institute of Solar Energy from the UPM and the Spanish Government Agency for Energy Diversification (IDAE).

Concentrator PV system on tracking unit built by Guascor Fotón at the UPM

The company is also working in three aditional solar plants using the same technology with a joint capacity of 3.5 MW in different parts of Spain.