International solar energy leaders, researchers discuss growing role in world energy and shared challenges for the future at 4th Multiterawatt Workshop | tidings

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Approximately 70 researchers from 14 countries gathered in California earlier this month to discuss progress toward deploying many terawatts of solar power around the globe for the transition to a sustainable energy system. Representatives from the US Department of Energy's National Renewable Energy Laboratory (NREL) held high-level discussions with international peers about the state of the photovoltaic (PV) industry.

This year marked the fourth Terawatt Workshop, led by representatives from NREL, Germany's Fraunhofer Institute for Solar Energy Systems, and Japan's National Institute of Advanced Industrial Science and Technology.

Except for a gap during COVID-19, the Terawatt Workshop has met every two years since 2016. That first meeting addressed the challenge of reaching 3 TW of global installed PV capacity by 2030. Participants expanded that vision to 2018 meeting, at about 10 terawatts and predicted that cumulative global PV capacity would reach one terawatt within the next five years. The world crossed that threshold in 2022.

The extraordinary learning curve in PV over the past few decades has resulted in continuous technological advances, major cost reductions and deployment growth often exceeding projections, said Nancy Haegel, director of the National Photovoltaic Center at NREL. Workshop participants were highly engaged in learning from each other and discussing what the next decade of growth and learning might bring.

She was joined at the conference by six colleagues from NREL: Teresa Barnes, Emily Warren, Kirstin Alberi, Joe Berry, Ingrid Repins, and Samantha Reese.

The workshop opened with reports and discussions on PV growth trajectories and challenges worldwide, with a focus on India, Europe, China, the United States, Australia and Kenya. This trip around the globe highlighted regional opportunities and challenges for PV growth and its contribution to meeting carbon dioxide emission reduction targets. A growing number of future scenarios show that PVs play major roles in helping countries move towards a sustainable energy system.

PV technology has shown increasing success and has become a mainstream for the world's energy supply. However, more research is needed to increase efficiency and create a circular economy, said Andreas Bett, director of the Fraunhofer Institute for Solar Energy Systems. PV is on track to provide most of the world's energy in a cost-effective, clean and sustainable way.

During the workshop, participants discussed PV technology innovation for the multiterawatt era, with a focus on tandem technology, which promises to significantly extend PV efficiency beyond existing limits. Tandem technologies combine two types of solar cells in one device, allowing increased absorption of light from the sun. Major research is underway, but there are still challenges to achieve industrial production of a more efficient and reliable tandem technology for terrestrial power generation. The workshop heard from leading researchers and industry partners on their progress and challenges in this area.

Another key topic was the question of long-term sustainability and turnover for the industry as it moves towards multiterawatt-scale future steady-state production, installation and replacement towards 2050. Workshop participants agreed that increased production is bringing a new set of research and development challenges to the PV community. Targeted research is needed to drive innovation and support industry efforts to continue reducing levels of embedded energy and carbon and raw material use, while driving global learning and increasing production diversification to continue as well. to advance performance and reliability.

As the PV industry has advanced and grown to lead the way for renewable energy in 2024, with the majority of new electricity generation capacity worldwide each year now coming from solar, it is preparing for the transition to its role to provide a majority of the world's energy needs.

Participants from the 2022 workshop suggested that around 75 terawatts or more of PV installed globally will be needed by 2050 to meet decarbonisation goals.

The National Institute of Advanced Industrial Science and Technology focuses on the creation and practical realization of technologies useful to Japanese industry and society and on bridging the gap between innovative technological seeds and commercialization. The Fraunhofer Institute for Solar Energy Systems stands out as the largest solar energy research institute in Europe.

NREL is the Department of Energy's only national laboratory devoted exclusively to research and analysis in renewable energy and sustainable energy technologies. Within PV programs, researchers support the development of new designs and manufacturing processes for solar materials, components, and systems, with an emphasis on improving performance, reliability, and service life.

Learn more about solar energy and photovoltaic research at NREL.