Tandem cells combine two types of solar cells applied on top of each other. Because each cell uses a different part of the sunlight spectrum, very high efficiencies beyond 30 percent can be achieved.

LEUVEN (Belgium), September 24, 2018 —Today, imec, the world-leading research and innovation hub in nanoelectronics, energy, and digital technology, unveiled its new tandem solar cell technologies, which pave the way to higher cell efficiencies of PV panels on roofs, as well as on vehicles or building-integrated applications such as solar cells in windows or facades. Tandem cells combine two types of solar cells applied on top of each other. Because each cell uses a different part of the sunlight spectrum, very high efficiencies beyond 30 percent can be achieved.

In its tandem cells, imec combines copper indium gallium selenide (CIGS) or silicon solar cells with perovskite, an innovative material that enables thin, transparent and cheap solar cells. As perovskite solar cells utilize the visible part of the light spectrum, they are ideally suited to combine with CIGS or Si solar cells, which utilize more the near-IR light portion of the spectrum instead. Tandem cells are therefore able to use sunlight more efficiently to produce electricity.

Imecs perovskite/silicon cell combines imecs 0.13cm² perovskite cell, developed within the Solliance collaboration, with a 4cm² silicon solar cell. The tandem cell achieves a conversion efficiency of 27.1 percent, which is higher than the best silicon solar cell (26.6 percent). Imecs perovskite/CIGS cell combines the 0.13cm² perovskite cell with a 3.8cm² CIGS module developed by ZSW (Zentrum für Solare Energiewirtschaft). This tandem cell achieves 24.6 percent efficiency, which is also higher than the current leading CIGS solar cells in the industry (22.9 percent).

"According to the International Technology Roadmap for PV (ITRPV), tandem solar cells are expected to appear in the market in 2021," stated Tom Aernouts, group leader thin-film PV at imec/Energyville. "At imec, we work on perovskite/silicon as well as on perovskite/CIGS tandems because each technology is directed towards different applications. For instance, silicon solar cells are especially suited for roofs and in solar cell parks, while CIGS thin-film solar cells can be produced on foils that could, in the future, be applied for building-integrated PV, turning facades and windows into electricity producers. We are pleased that our new perovskite-based tandem cell technologies will further enhance the capabilities of these solar cells towards 30 percent."




About imec
Imec is the world-leading research and innovation hub in nanoelectronics, energy and digital technologies. The combination of our widely acclaimed leadership in microchip technology and profound software and ICT expertise is what makes us unique. By leveraging our world-class infrastructure and local and global ecosystem of partners across a multitude of industries, we create groundbreaking innovation in application domains such as healthcare, smart cities and mobility, logistics and manufacturing, energy and education.

Imec is a partner in EnergyVille (www.energyville.be). EnergyVille is a collaboration of the Flemish research centers KU Leuven, VITO, imec and UHasselt in the field of sustainable energy and intelligent energy systems, and a partner in Solliance (www.solliance.eu), a partnership of R&D organizations from the Netherlands, Belgium and Germany working in thin film photovoltaic solar energy.
As a trusted partner for companies, start-ups and universities we bring together more than 4,000 brilliant minds from over 85 nationalities. Imec is headquartered in Leuven, Belgium and has distributed R&D groups at a number of Flemish universities, in the Netherlands, Taiwan, USA, China, and offices in India and Japan. In 2017, imec's revenue (P&L) totaled 546 million euro. Further information on imec can be found at www.imec-int.com.

Imec is a registered trademark for the activities of IMEC International (a legal entity set up under Belgian law as a "stichting van openbaar nut"), imec Belgium (IMEC vzw supported by the Flemish Government), imec the Netherlands (Stichting IMEC Nederland, part of Holst Centre which is supported by the Dutch Government), imec Taiwan (IMEC Taiwan Co.) and imec China (IMEC Microelectronics (Shanghai) Co. Ltd.) and imec India (Imec India Private Limited), imec Florida (IMEC USA nanoelectronics design center).

Contact: Hanne Degans, Press communications manager, +32 16 28 17 69 // +32 486 06 51 75 // Hanne.Degans@imec.be

About Solliance
Solliance is a partnership of R&D organizations from the Netherlands, Belgium and Germany working in thin film photovoltaic solar energy (TFPV). In order to strengthen the regions position as a world player in PV, Solliance is creating the required synergy by consolidating and coordinating the activities of 250 researchers in industry, at research institutes and universities.

Various state-of-the-art laboratories and pilot production lines are jointly used for dedicated research programs which are executed in close cooperation with the solar business community.
Solliance partners are: imec, TNO, ECN part of TNO, TU/e, Forschungszentrum Jülich, University Hasselt and Delft University of Technology.

Solliance offers participation in its research programs and opens up its lab facilities to new entrants, either from industry or in research. On the basis of clear Intellectual Property (IP) agreements, each industrial partner can participate in this research effort, or alternatively, hire equipment and experts to further develop its own technology.

About ZSW
The Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (Centre for Solar Energy and Hydrogen Research Baden-Württemberg, ZSW) is one of the leading institutes for applied research in the areas of photovoltaics, renewable fuels, battery technology, fuel cells and energy system analysis. There are currently around 250 scientists, engineers and technicians employed at ZSWs three locations in Stuttgart, Ulm and Widderstall. In addition, there are 90 research and student assistants.

Contact: Claudia Brusdeylins, Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW) / Centre for Solar Energy and Hydrogen Research (ZSW), Meitnerstr. 1, 70563 Stuttgart, Tel. +49 711 7870-278, claudia.brusdeylins@zsw-bw.de, www.zsw-bw.de

About Energyville
EnergyVille is a collaboration between the Flemish research partners KU Leuven, VITO, imec and UHasselt in the field of sustainable energy and intelligent energy systems. Our researchers provide expertise to industry and public authorities on energy-efficient buildings and intelligent networks for a sustainable urban environment. This includes, for example, smart grids and advanced district heating and cooling.
One of the objectives of EnergyVille is to become one of the top five European institutes in innovative energy research. In this context, the center was embedded in major national and international networks right from the start. It covers research, development, training and innovative industrial activities under one name and in close collaboration with local, regional and international partners.
EnergyVille aims to be a driver in the Thor science park in Genk in the areas of research, business development and employment creation. The research center is supported by the city of Genk, the Flemish Government, the Province of Limburg, LRM, Nuhma, POM Limburg and the European structural funds.