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Abstract: In the past years various methods have been developed to estimate high-resolution solar potential in urban areas, by simulating solar irradiance over surface models that originate from remote sensing data. In general, this requires discretisation of solar irradiance models that estimate direct, reflective, and diffuse irradiances. The latter is most accurately estimated by an anisotropic model, where the hemispherical sky dome from arbitrary surface’s viewpoint consists of the horizon, the circumsolar and sky regions. Such model can be modified to incorporate the effects of shadowing from obstruction with a view factor for each sky region. However, state-of-the-art using such models for estimating solar potential in urban areas, only considers the sky view factor, and not circumsolar view factor, due to high computational load. In this paper, a novel parallelisation of solar potential estimation is proposed by using General Purpose computing on Graphics Processing Units (GPGPU). Modified anisotropic Perez model is used by considering diffuse shadowing with all three sky view factors. Moreover, we provide validation based on sensitivity analysis of the method’s accuracy with independent meteorological measurements, by changing circumsolar sky region’s half-angle and resolution of the hemispherical sky dome. Finally, the presented method using GPPGU was compared to multithreaded Central Processing Unit (CPU) approach, where on average a 70x computational speedup was achieved. Finally, the proposed method was applied over a urban area, obtained from Light Detection And Ranging (LiDAR) data, where the computation of solar potential was performed in a reasonable time.
Keywords: solar energy, solar potential, anisotropic diffuse irradiance, LiDAR, GPGPU
Published in DKUM: 17.12.2024; Views: 0; Downloads: 3
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Abstract: The attempt at a more sustainable land use by increasing urban density may have a negative effect on the daylighting of residential buildings. In densely built areas, obstructions generated by the surrounding buildings can substantially reduce the available amount of daylight, causing poorly daylit spaces and a less healthy indoor environment with higher electricity consumption as a consequence of artificial lighting. European standard EN 17037, Daylight in Buildings, was established in 2018 to ensure appropriately daylit spaces. In this paper, a three-step methodology was developed to investigate the relationship between certain urban planning parameters and the daylighting of a typical room defined by specific (Slovenian) legislative restrictions about its geometry and minimum required window to floor area ratio, in order to establish the maximum densities of residential developments still fulfilling the minimum requirements for daylight provision defined by EN 17037. The results show that a relatively low urban density is required to fulfil the stipulations for minimum daylight provision for the deepest permissible room according to the Slovenian legislation. The impact of the development floor area ratio on the daylighting potential of buildings was identified as significant, followed by the site coverage, development layout, and building typology. Furthermore, the developed methodological approach clearly demonstrates a substantial potential for application in urban planning, with indoor daylight environmental conditions being linked to the planning of residential developments in the earliest stages of the project.
Keywords: sustainable urban planning, daylighting, vertical daylight factor, residential developments, solar potential
Published in DKUM: 14.07.2023; Views: 510; Downloads: 60
Full text (4,82 MB)
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