Rapid and uncontrolled urbanization is continuously increasing buildings’ energy consumption and greenhouse gas emissions into the atmosphere. In this scenario, solar energy integrated into the built environment can play an important role in optimizing the use of renewable energy sources on urban surfaces. Preliminary solar analyses to map the solar accessibility and solar potential of building surfaces (roofs and façades) should become a common practice among urban planners, architects, and public authorities. This paper presents an approach to support urban actors to assess solar energy potential at the neighborhood scale and to address the use of solar energy by considering overshadowing effects and solar inter-building reflections in accordance with urban morphology and building characteristics. The approach starts with urban analysis and solar irradiation analysis to elaborate solar mapping of façades and roofs. Data processing allows assessment of the solar potential of the whole case study neighborhood of Sluppen in Trondheim (Norway) by localizing the most radiated parts of buildings’ surfaces. Reduction factors defined by a new method are used to estimate the final solar potential considering shadowing caused by the presence of buildings’ architectural elements (e.g., glazed surfaces, balconies, external staircases, projections) and self-shading. Finally, rough estimation of solar energy generation is assessed by providing preliminary recommendations for solar photovoltaic (PV) systems suited to local conditions. Results show that depending on urban morphology and buildings’ shapes, PV systems can cover more than 40% of the total buildings’ energy needs in Trondheim.

The increasing demand for nearly zero energy buildings is rapidly contributing to changing the design criteria in architecture and concept of the building envelope. Today, photovoltaics (PV) is one of the most reliable technologies for integration in the built environment, and building-integrated photovoltaics (BIPV) is introducing a different notion of ‘energy integrability’ into practice. The difficulty of undertaking, from the first design stages, a really integrative approach towards energy (PV and building requirements) is today still one of the strongest barriers to the rise of the BIPV market. Likewise, the same uncertainty affects the economic aspects, objects of this paper, since BIPV systems are often evaluated similar to conventional installations. The typical consequence is to neglect their added value such as the multi-functionality of the system and therefore showing limited advantages of BIPV. Scope of this paper, starting from a multi-criteria approach, is to outline a new methodology for evaluating the cost-effectiveness of BIPV for the building skin. This method, based on a life-cycle costing approach and on the assessment of the whole building envelope solution, is expected to support architects during the early design phase in the research of the optimal design of BIPV, synergistically taking into account both PV and building quality. A comparison with conventional building elements and different PV technologies is also presented in order to strengthen the impact of the proposed methodology.

Solar has confirmed its dominance among all power generation technologies, and along with the demand for zero-emission buildings, Photovoltaics (PV) is contributing to transforming the building skin. More than 200 products for Building Integrated Photovoltaics (BIPV) are commercialized nowadays in the EU market. However, only 1–3% of all PV installations are BIPV due to the weak penetration in the construction sector. At the state of the art, the sector lacks a specific analysis from a construction technology perspective, describing the dynamics and the traits that BIPV innovation articulates on construction and architectural processes. The authors, elaborating a new model from the building technology sector to explore the relationship between PV technology and architectural innovation, aim to identify the main principles, forms, and approaches that describe the structural organization of the “integrability” concept of PV in buildings. This study applies the method to a database of 233 real buildings located in Switzerland, a unique country leading with a 10% BIPV rate on PV installations documented between the years 1997 and 2023. The novel findings of the research suggest the definition of the levels of innovation and the reference traits of the innovative process of BIPV in the Swiss construction sector, which can also be used in other practical applications and contexts. The results of the paper are expected to impact both the scientific academy and the key players from the construction sector, encouraging the adoption of an integrated research and design approach to revolutionize the energy role of building skins with PV.