NTNU-SINTEF SolarNet: A solar irradiation monitoring network at high latitudesManni, M; Nocente, A; Bellmann, M; Völler, S; Sabatino, M Di; Lobaccaro, G
doi: 10.1088/1742-6596/2600/4/042010pmid: N/A
This study presents a monitoring network for solar irradiation at high latitudes, called NTNU-SINTEF SolarNet. The network collects, with a time resolution ranging from seconds to hours, solar irradiance data, e.g. global horizontal irradiation, diffuse horizontal irradiation, direct normal irradiation, global tilted irradiation, solar energy generation, which are required in solar irradiation modelling in built environments. The network will be used for specific applications, such as (i) anomalies detection, (ii) influences of ground albedo, and (iii) ageing/degradation of solar modules, that are described in this paper. Some characteristics that make the NTNU-SINTEF SolarNet relevant for solar energy research at high latitudes are identified: short distances among the sensors, the ease of data accessibility, the use of the same sensor typologies, and different solar module technologies. The research holds the potential to boost the solar energy digitalization, impacting on several aspects such as predictive and adaptive control strategies for energy management, design of renewable energy system, multi-scale optimization and efficient exploitation of solar energy.
Increasing PV solar collection using the upper edges in balconiesValdivia-Sisniegas, R H
doi: 10.1088/1742-6596/2600/4/042009pmid: N/A
The current increment of electric prices over the world has created economic problems, but it is also a turning point to a serious rethink about the dependency on fossil fuels. Adapting balconies to produce energy with mini PV installations is increasing in many countries, because not only it reduces costs; but also promotes the energy transition and adaptation as well “plug&save” systems has made the access to photovoltaic electricity easier in existing apartments by using the balustrade or parapets in balconies. Moreover, the stock of multi-story building apartments represents a significant number of dwellings, which is in favor of density and sustainable cities. The current evolution of the market is producing lightweight panels, which combined with new patented devices can improve the solar incidence collection; thus, using upper edges in balconies can result in an easy, and flexible way to install and maintain.
Solar potential on facades at urban scale: an integrated approach combining solar and digital building modellingDesthieux, G; Gressin, A; Raybaud, B; Ingensand, J
doi: 10.1088/1742-6596/2600/4/042004pmid: N/A
The paper presents an integrated approach to improve the solar radiation modelling on facades in large-scale built-up areas. The modelling of the built environment must first be improved in terms of level of detail. Thus, from aerial oblique images, a digital twin of the urban scene is created, allowing to process the facades as textured objects and to detect windows using an artificial intelligence image processing. Reflected radiation is significant on vertical surfaces, but complex to model on large areas. The developed model is based on a simplified radiosity approach, which reduces the volume of analysis, storage and thus the computation time, while producing reliable results. A demonstration of the integrated tool is presented for an urban area in Geneva (1 km2), including a solar energy balance assessment for one of the buildings using the results from the solar modelling. The perspective is to generalise the approach to a larger scale and to complete the solar cadastre of the roofs of the Greater Geneva area with the facades.
Estimating surface utilization factors for BIPV applications using pix2pix on street captured façade imagesDuran, Ayça; Waibel, Christoph; Schlueter, Arno
doi: 10.1088/1742-6596/2600/4/042005pmid: N/A
While techniques for assessing solar potential, particularly on roofs, are well-established, estimating solar potential on building facades often requires more work due to the complexity of urban features and the elaborate design of building facades. Existing methods to assess the solar potential of building facades often neglect the characteristics of individual facades. This study presents an image-based method for a more accurate estimation of the PV potential of facades. The proposed method is composed of four steps: (1) data acquisition, preprocessing, and manual labeling, (2) training a pixel-wise semantic image segmentation model based on Generative Adversarial Networks (GANs), (3) color content analysis of segmented images, and (4) estimating the annual solar energy potential. We apply the proposed workflow to several buildings in Zurich, Switzerland, and evaluate segmentation quality and resulting changes in façade surface utilization factors. In a comparative analysis between the widely used web-based solar potential assessment tools, Sonnenfassade, Global Solar Atlas and the simulation software Climate Studio, we demonstrate the downstream impact of surface utilization factors on resulting solar potentials. Considerable deviations in façade availability for BIPV deployments among the various tools as compared to our segmentation approach indicate the potential impact of the proposed method on policy-making and the benefits for BIPV design and planning.
Parametric design of a residential building system through solar energy potential: the case of Guelma, AlgeriaMedjeldi, Z; Kirati, A; Dechaicha, A; Alkama, D
doi: 10.1088/1742-6596/2600/4/042012pmid: N/A
To evaluate the potential of retrofitting roofs of residential buildings in Algeria with building integrated photovoltaics (BIPV). A case study of a family residential building in the city of Guelma, was selected to receive building-integrated photovoltaic (BIPV) systems as a retrofit to their roofs using Rhinoceros software and plugins Grasshopper, Ladybug, and Honeybee, adding photovoltaic panels on the roof taking into account the study of solar radiation analysis on the building, and meteorological data from Meteonorm Software 7.3. The method used, is based on measured data for final energy consumption (yearly average of 14600 kWh), building morphology, and photovoltaic module parameters. The results of the renovation of roofs with building-integrated photovoltaic solutions are presented for the existing residential building, it is also shown that a small photovoltaic area on the roofs can meet the demand of the buildings. The results identify the aspects that need to be improved in the development of future design tools and highlight the importance of integrating parametric design software and simulation tools for BIPV systems at the preliminary design stage, to ensure good building performance, both in terms of comfort and energy performance.
Experimental energy performance in electrified renewable energy-sharing communityKim, Min-Hwi; Kim, Haneol; Kim, Jong-Kyu; Ahn, Young-Sub
doi: 10.1088/1742-6596/2600/4/042017pmid: N/A
In this study, the empirical results of renewable energy self-sufficiency for communities consisting of residential and nonresidential buildings were analyzed. These buildings were combined with a grid-connected electrified community. The community was primarily powered by building-integrated photovoltaic (BIPV) systems, and cooling and heating water were supplied by geothermal and hydrothermal source heat pump systems. The community building comprised 56 detached houses and two office buildings. The community’s primary electricity generation was provided by a 500 kWp BIPV, approximately 7.1 kWp installed per household. This community had facilities that provided cooling, heating, and domestic hot water from heat supply stations. Thermal energy for cooling and heating was mainly generated by geothermal and sewage water-source heat pumps, stored in a daily heat storage tank, and supplied to households. Based on the analysis using ISO 13790-based software, the cooling and heating requirements were 51 and 42 kWh/m2, respectively. The cooling and heating requirements were 49 and 44 kWh/m2, and a difference of approximately 5% between the simulation and experiment results was observed. Consequently, the annual zero-net energy balance was 138.2% when the plug load was excluded but 46.8% when the plug and electric-vehicle electricity loads were included.
What is the net PV energy production in Switzerland and how can we maximize it?Martinez-Alcaraz, P.; Serra-Coch, G.; Alonso-Montolio, C.; Coch, H.
doi: 10.1088/1742-6596/2600/4/042013pmid: N/A
Maximizing solar energy production in Switzerland is key to meet energy transition goals. Understanding in detail the current situation, and the potential for expansion is important to develop effective strategies. With this study, we want to contribute to federal and academic efforts to measure solar energy by estimating the net energy produced by photovoltaic (PV) installations when considering their embodied energy. We calculated the values of all energy produced by PV installations across Switzerland from 1991-2021 and subtracted the embodied energy used to manufacture the PV panels and their mounting system. We considered four different types: freestanding, attached-complex, attached-simple and integrated, with progressively decreasing values of embodied energy for the supporting structure. The results show that in 2022, 50% of PV installations were producing net energy, which accounts for an accumulated historical value of 1.000 GWh, implying that 6% of the historical PV generation is net energy. If mounting systems were minimized, the accumulated net energy would reach 23%, showing the importance of integrating PV panels in building elements. These findings suggest that policies to support the diffusion of photovoltaic panels should also ensure long term use of existing installations and consider the mounting systems’ embodied energy for new ones.
A Review and Analysis of Energy Systems Planning Models and Tools for Renewable Energy Integration in CitiesYazdanie, M; Orehounig, K
doi: 10.1088/1742-6596/2600/4/042007pmid: N/A
This review study evaluates a range of urban energy system planning models/tools (UEPMs) with respect to their capabilities to consider, identify, integrate and scale up renewable energy technology (RET) deployment in cities. Working with local stakeholders, we define twenty weighted evaluation criteria in order to assess UEPM capabilities using a multi-criteria decision analysis approach. We then discuss the top-ranking UEPMs in the context of our aims. We also survey and interview UEPM practitioners and experts in order to gain a better understanding of their needs, challenges and perceived barriers in the field. The outcomes of this work are useful for both UEPM users and researchers in order to improve the uptake and application of UEPMs by decision-makers to develop sustainable energy plans.
Upscaling potential of BIPV for public housing typologies in SingaporeGester, Maximilian; Waibel, Christoph; Grammatas, Argyrios; Sing, Tien Foo; Schlueter, Arno
doi: 10.1088/1742-6596/2600/4/042008pmid: N/A
This paper assesses the upscaling potential of Building Integrated Photovoltaics (BIPV) in the public housing stock of Singapore. While the installation of rooftop PV is gaining rapid traction in the city-state, there are still only few existing projects with façade PV. Considering the large share of façade areas available, this paper aims to identify the most suitable building typology for BIPV integration. The research methodologies include a city-wide analysis of solar potentials, photogrammetry-based solar assessments of the four most common housing typologies, and a load-matching analysis of a typical contemporary apartment unit. Furthermore, we conduct a qualitative analysis through interviews with public and private stakeholders, to understand the drivers and barriers of BIPV in Singapore. Our results reveal districts with the the highest total electricity generation potential such as “Bedok”, or others with larger façade than roof PV-potential such as “Bukit Merah”, where buildings often feature eastwards-oriented façades with low window-to-wall ratio, making them ideal for electricity production in the morning hours. Due to higher cloud coverage in the afternoon, Westward-oriented façades have an overall lower potential. The load-matching analysis shows, however, that peak demand in the morning and evening can generally not be met by BIPV only. The analysis of building typologies reveals that geometrically simpler linear buildings built in the 70’s and 80’s have higher total PV generation potential due to larger roof areas and less obstructed façades. The contemporary point towers with irregular façade surfaces show a larger fraction of façade BIPV electricity generation per floor area, exceeding the share of electricity produced on rooftops. A customized BIPV system will be promising for these newer building typologies, supported by soft factors identified in the interviews.
Performance measurements on WISC collectors under artificial environmental conditionsPauletta, S; Duret, A; Dupont, G; Jobard, X
doi: 10.1088/1742-6596/2600/4/042014pmid: N/A
In the framework of the TriSolHP project, aimed at estimating the impact of improved heat pump technologies for decarbonization of non-retrofitted multifamily buildings in urban districts, a new type of PVT WISC (a photovoltaic-thermal wind and/or infrared sensitive collector) has been extensively tested in a climatic room without light input. The measurement campaign focused on the impact of airflow over the collector heat transfer coefficient for different installation layouts and when covered in ice. Measurement data were compared to TRNSYS simulations to gain an insight over the uncertainties affecting the performance models available in literature for this type of WISC.