PhD defence by Nicholas Christopher Riedel-Lyngskær

Title: Characterization and modeling of bifacial photovoltaic modules and systems

Supervisors

• Main Supervisor: Associate Professor Sergiu V. Spătaru, Department of Electrical and Photonics Engineering, DTU, Denmark
• Co-Supervisor: Senior Researcher Michael L. Jakobsen, Department of Electrical and Photonics Engineering, DTU, Denmark
• Industrial Supervisor: PhD Jan Vedde, European Energy A/S

Assessment committee

• Senior Researcher Kaushik Das, Department of Wind and Energy Systems, DTU; Denmark
• Professor Wilfred van Sark, Institute of Sustainable Development, Utrecht University, Netherlands
• PhD Jonathan Leloux, LuciSun, Belgium

Master of the Ceremony

• Senior Researcher, Stela Canulescu, Department of Electrical and Photonics Engineering, DTU, Denmark

Abstract:

This thesis provides insights into the measurement and modeling practices of bifacial photovoltaics (BPV). BPV is a solar technology that produces electricity from light shining on the front and back sides of the cell. The first BPV cell concepts date back ~60 years, but the widespread adoption of BPV modules and systems started only in the last ~5 years. This work therefore addresses some of the open questions that renewable energy project developers have surrounding BPV, such as the accuracy of BPV energy yield modeling, the best-practices for performance monitoring of BPV plants, and the optimal use of BPV modules in utility-scale applications.

In Chapter 2, an extensive BPV model validation effort is performed wherein the results show that state-of-the-art BPV performance models add ~0.5% uncertainty to the modeling process; Chapter 3 examines the nuances of the light on the backside of BPV systems and provides simplified correlations that may improve the accuracy of BPV energy modeling; Chapter 4 describes a novel yet straightforward approach to measure backside and frontside irradiance using a pair of BPV reference panels. Finally, Chapter 5 studies the economics of increasing albedo (ground reflectivity) in large-scale BPV plants and provides practical recommendations for the implementation hereof.