Towards terawatt production of c-Si solar photovoltaics.


TERASUN: Towards terawatt production of c-Si solar photovoltaics.

TERASUN aims to develop technologies making c-Si PV solar cells more efficient and cost-effective. The project innovates on Si heterojunction (SHJ) solar cell technology, currently holding the c-Si power conversion efficiency record of 26.81% for single junction c-Si solar cells. By targeting higher efficiencies and lower costs, TERASUN paves the way for mass production of improved SHJ solar cells.


TERASUN develops:


  • Nanophotonic structures on module cover glass to minimise reflection (maximise absorption) andimprove anti-soiling properties and improving the overall performance of the module, which will allow for reduced silicon consumption and higher efficiencies;
  • Innovative texturisation, including micro- and nanostructures for optimal light-trapping to enable the use ultrathin crystalline Si solar cells;
  • Novel heterojunction contacts based on metal-oxide layers implemented in interdigitated back contact (IBC) SHJ solar cells for very high efficiencies, and low-cost surface passivation for advanced surface structures;
  • Low-cost metallisation, replacing silver with copper to move towards a technology ready for terawatt production scale; and
  • Direct bandgap architectures for implementation in IBC SHJ solar cells.


These developments aim to help with approaching the fundamental limit of 29.43% on cell level and reducing cell-to-module losses for optimised energy yield. The strategic choice of materials (Cu, Al-doped Zn oxide, Sn oxide) is key to reduce the costs and supply chain risks. Environmental, economic and performance data associated with the developments are also gathered, evaluated and used to develop an algorithm based on multi-disciplinary design optimisation to create the TERASUN decision support tool (DST). The DST aims to provide stakeholders from industry and policymakers with: (i) recommendations related to the most promising technologies and (ii) a clear roadmap for the technologies developed in TERASUN towards TRL9.

Our main tasks

  • Technical project management and coordination.
  • Financial and administrative project management.
  • Project progress and quality monitoring, risk management and evaluation.
  • Data management and open science.
  • KPI definition, evaluation, and validation.
  • Data collection of materials and processes used for TERASUN PV devices.
  • Assessment of materials and processes for solar modules.
  • Economic, environmental and sustainability data analysis and evaluation.
  • Stakeholder decision support tool.
  • Module creation for the TERASUN DST.
  • Final release of the TERASUN tool.



Start date – finish date

06 / 2024 - 05 / 2027

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement Nº 101147545