New Hybrid Solar Energy Device Combines Photovoltaic Power with Molecular Thermal Storage

In a major breakthrough for renewable energy, an international research team has developed the first hybrid device that combines a silicon solar cell with a cutting-edge storage system called Molecular Solar Thermal Energy Storage (MOST). This innovative technology, led by ICREA professor Kasper Moth-Poulsen from the Universitat Politècnica de Catalunya (UPC), is designed to address the challenges of intermittent solar energy production and fluctuating energy demand.

The MOST system uses organic molecules that, when exposed to ultraviolet light, undergo a chemical transformation to store energy for future use. These molecules also act as an optical filter, cooling the photovoltaic cell by blocking photons that would typically generate heat and reduce efficiency. The combined system enables simultaneous energy generation and storage, marking a significant advancement in solar technology.

Importantly, the MOST system relies on abundant materials such as carbon, hydrogen, oxygen, and nitrogen, offering a more sustainable alternative to conventional battery technologies that depend on scarce and unsustainable resources. The hybrid device achieves a record energy storage efficiency of 2.3% for molecular solar thermal energy and lowers photovoltaic cell temperatures by up to 8°C, enhancing overall efficiency by 12.6%. The system’s solar utilization efficiency reaches 14.9%, outperforming previous hybrid technologies.

The results of this research have been published in the journal Joule. The development is part of the ERC PHOTHERM and EU FET-PROACT MOST projects, supported by 6.3 million euros in European Union funding. The team also includes researchers from the University of Cambridge (UK), Chalmers University of Technology (Sweden), and the Institute of Materials Science of Barcelona (ICMAB-CSIC).

This hybrid technology is set to play a critical role in the global shift toward clean energy, offering a more efficient and sustainable solution for energy production and storage.