ABSTRACT Five decades of 100% renewable energy (RE) systems research established a vibrant research field that increasingly builds on solar photovoltaics (PV). A database on 100% RE systems articles has been used to analyse the changing role of solar PV from 1975 to 2025. Analysing the database, 29 milestone articles have been identified that introduced a new element for the role of solar PV within the research field. These milestones were reached in all decades, and the four largest groups are (i) around visionary scoping of the role of PV, (ii) advances in PV system applications, (iii) expanding economic insights and (iv) methodological advancements leading to more realistic descriptions of PV in energy‐industry systems. In most advanced 100% RE system analyses, solar PV can be described in up to eight PV system applications, in hourly resolution, in interconnected multi‐node study designs, covering all sectors spanning power, heat, transport, industry, desalination and carbon dioxide removal, with comprehensive power‐to‐X routes, and broad flexibility portfolios, such as grids, storage and demand response with diversified sector coupling and energy conversion routes. However, even a basic PV system differentiation of ground‐mounted utility‐scale and rooftop PV is far from standard as only 16% of all studies include this differentiation. On a global level, studies find increasingly a PV share of 60%–80% in total primary energy supply around mid‐century or beyond with a 61% projected average across transition studies. Solar PV has emerged as a core solution for a sustainable civilisation on its path towards the Solar Age.
Breyer et al. (Fri,) studied this question.