The initial concept for combining agriculture and photovoltaics instead of their competition for soil, was conceived by the founder of the Fraunhofer ISE, Prof. Dr. Adolf Götzberger, and his colleague, Dr. Armin Zastrow, as early as 1981. This might be considered the birth of agrivoltaic systems, whereas the tailored photovoltaics for this purpose may be called agrivoltaic devices. While so far today's photovoltaic infrastructure has followed the economics of scale resulting in huge and monotonic power plants, only more recently, interest in agrivoltaics has been steadily increasing with more and more projects getting realized around the world.

Reasons for the rising interest in such smart combinations between crop growth and electricity generation are due to an increasing competition about land use for either energy or food production in many regions of the world. Even though ground-mounted utility-scale PV systems show a much (up to 100x) higher efficiency in the annual energy yield than the production of so-called biofuels, they still do compete with local food production. Thus, increased combined yield of crop and electricity production, as compared to either single option (e.g., on neighboring fields), is highly attractive. In comparison to agriculture alone, agrivoltaics can lower stress arising from intense sunshine, intense rain or hail, and high evapotranspiration rates. Details of agrivoltaic systems may also depend on transparency in terms of spectrum or opaqueness, free standing or greenhouse installations, and many more factors to be researched.

At the verge towards mass adoption of agrivoltaics, this special section of Journal of Photonics for Energy (JPE) seeks to highlight not only materials research and device engineering but also application developments in agrivoltaic systems. We welcome articles reporting new research in the field, as well as perspectives and review articles. Potential topics include but are not limited to: 

Presentation and discussion of various different use cases for agrivoltaics Development of agrivoltaic installations for use in specific areas of application, respectively agricultural fields Assessing the photovoltaic, the agricultural, and the combined performance or yield of agrivoltaic systems Assessing the impact of agrivoltaic installations on crop growth Strategies for increasing the social and political acceptance of agrivoltaics Removing administrative barriers for agrivoltaic installations Choice and applicability of photovoltaic panels from different technologies Integration of photovoltaics into existing agrivoltaic greenhouses or polytunnels

Development of novel solar cells and novel modules with specific properties useful for agrivoltaics Development of materials for photovoltaics applied within agrivoltaic systems Optical modelling and optical adaptation of photovoltaic devices for optimal light propagation or spectral use Novel strategies for thin-film, organic, or other novel photovoltaic technologies for agrivoltaic systems Design and assessment of system components for agrivoltaics Simulations of agrivoltaic systems Return of investment and other cost analyses governing the success of agrivoltaics Region- and climate-specific agrivoltaic solutions

The implementation of photovoltaics (PV) has grown tremendously over the last decade with the global installed capacity of PV now exceeding a terawatt. Much of this growth has been driven by the economy of scale, global awareness of energy issues and governmental policy, and technological innovations in terms of (predominantly) silicon and thin film manufacturing. However, further improvements in performance and implementation of PV require the development of new materials and architectures that enable not only enable further reductions in cost, but also consider materials sustainability and improvements in efficiency beyond the single gap limit. In this JPE special issue, papers are sought that consider advanced concepts that have the potential to enable a paradigm shift in PV energy conversion “Exceeding the Detailed Balance Limit.” These include (but are not limited to):

• Recent developments in hot carrier solar cells
• Intermediate band solar cells, as well as other pioneering technologies in reducing thermal losses and transmission in solar cells
• Up/down conversion (e.g. singlet fission, quantum cutting etc.) and carrier multiplication/multiple-exciton generation
• Articles that address spectral splitting and light management
• Nanophotonics and plasmonics
• Thermodynamic considerations and system modeling
• Novel materials and structures — both bulk and quantum in nature