Empa achieves record 20.4% efficiency for flexible thin film

Facebook
Twitter
LinkedIn
Reddit
Email

Scientists at Empa, the Swiss Federal Laboratories for Materials Science and Technology, have developed thin film solar cells on flexible polymer foils with a new record efficiency of 20.4% for converting sunlight into electricity.

Empa said the cells are based on CIGS semiconducting material (copper indium gallium (di)selenide) known for its potential to provide cost-effective solar electricity. The technology is awaiting scale-up for industrial applications.

This article requires Premium SubscriptionBasic (FREE) Subscription

Try Premium for just $1

  • Full premium access for the first month at only $1
  • Converts to an annual rate after 30 days unless cancelled
  • Cancel anytime during the trial period

Premium Benefits

  • Expert industry analysis and interviews
  • Digital access to PV Tech Power journal
  • Exclusive event discounts

Or get the full Premium subscription right away

Or continue reading this article for free

To make solar electricity affordable on a large scale, scientists and engineers the world over have long been trying to develop a low-cost solar cell, which is both highly efficient and easy to manufacture with high throughput.

The team at Empa's Laboratory for Thin Film and Photovoltaics, led by Ayodhya N. Tiwari, achieved a record 20.4% energy conversion efficiency for thin film CIGS solar cells on flexible polymer substrates, a huge improvement over the previous record of 18.7% achieved by the same team in May 2011.

Tiwari’s team has been investigating and developing various thin film solar cell technologies for some time. Over the years the laboratory has boosted the photovoltaic conversion efficiency of flexible CIGS solar cells time and again, from 12.8% in 1999 – the group’s first world record – to 14.1% in 2005, 17.6% in 2010 and 18.7% in 2011.
 

Read Next

October 2, 2026
Welcome to the PV Tech Best of the Week roundup, covering the week’s biggest stories from the global solar PV industry.
Premium
October 2, 2026
The US solar industry is contending with variable module quality as new suppliers jostle to serve this lucrative market.
October 2, 2026
Independent power producer (IPP) ContourGlobal and community-owned public power utility Platte River Power Authority have completed construction of a 324MW solar PV complex in the US state of Colorado.
October 2, 2026
Germany is on course to produce over 600,000 tonnes of solar PV waste material by 2030, potentially worth billions in aluminium and silver.
October 2, 2026
Renalfa IPP and Danish renewables developer Eurowind Energy have began commercial operations at a 242MWp solar-plus-storage hybrid park in Bulgaria.
October 2, 2026
First Solar has filed a patent lawsuit against JA and some of its subsidiaries, as well as American Panel Solutions, a wholly-owned subsidiary of Corning.

Upcoming Events

Solar Media Events
October 13, 2026
San Francisco Bay Area, USA
Solar Media Events
November 3, 2026
Málaga, Spain
Solar Media Events
November 24, 2026
Warsaw, Poland
Solar Media Events
February 2, 2027
London, UK