A Methodological Analysis Approach to Assess Solar Energy Potential at the Neighborhood Scale

Abstract

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.

Solar Energy in Urban Planning: Lesson Learned and Recommendations from Six Italian Case Studies

“…The advantages of building-integrated photovoltaics (BIPV) and solar thermal (BIST) are manifold: unused surfaces can be turned into active energy generators [13], losses associated with transmission and distribution of electricity are reduced thanks to on-site production [14], and higher energy flexibility toward extreme weather conditions is guaranteed [3]. On the other hand, the installation of such systems in urban areas, especially on vertical surfaces (i.e., facades), requires considering complex phenomena such as inter-building solar reflections and overshadowing effects [15][16][17], and other energy and climate-related issues, such as high surface temperature [18] and fire hazard [19]. The visibility and the socio-cultural sensitivity impact of the systems should also be considered [20][21][22][23].…”

Multicriteria roof sorting for the integration of photovoltaic systems in urban environments

“…Sorting processes have been widely used in cities. They take the form of GIS tools called solar cadastres (IRENA, 2019b;Kanters et al, 2014;Lobaccaro et al, 2019b). The solar cadastre of a city is a geographical interface, which makes it possible to know how much sunlight a given roof, building, home or a part of them receives.…”

“…The solar cadastre of a city is a geographical interface, which makes it possible to know how much sunlight a given roof, building, home or a part of them receives. The cadastres reviewed in (IRENA, 2019b;Kanters et al, 2014;Lobaccaro et al, 2019b) all sorted roofs by considering their solar irradiation i.e. the energy received yearly per square meter.…”

“…To that aim, the shaded areas which correspond in the present case to the parts of the roofs receiving less than 1000 kWh.y/m² are removed from the total surface area of the roof. There are no requirements for the lower limit, and but 1000 kWh.y/m² is a common value used in different solar cadastres (Lobaccaro et al, 2019b).…”

Assessment on the Efficiency of an Active Solar Thermal Facade: Study of the Effect of Dynamic Parameters and Experimental Analysis When Coupled/Uncoupled to a Heat Pump

“…In such a scenario, ASTF also represents a very promising concept [3,4] aiming to incorporate Renewable Energy Sources (RES) to the building. As the interface connecting the interior of the building, where comfort is a priority, to the exterior under variable environmental conditions, the opportunity directly assigned to the facade as a bridge to connect renewable energy sources to the building has been clearly identified [5][6][7]. There is a significant variety of technologies for ASTFs with different degrees of sophistication [8,9].…”