Review and harmonization of the life-cycle global warming impact of PV-powered hydrogen production by electrolysis

This work presents a review of life-cycle assessment (LCA) studies of hydrogen electrolysis using power from photovoltaic (PV) systems. The paper discusses the assumptions, strengths and weaknesses of 13 LCA studies and identifies the causes of the environmental impact. Differences in assumptions of system boundaries, system sizes, evaluation methods, and functional units make it challenging to directly compare the Global Warming Potential (GWP) resulting from different studies. To simplify this process, 13 selected LCA studies on PV-powered hydrogen production have been harmonized following a consistent framework described by this paper. The harmonized GWP values vary from 0.7 to 6.6 kg CO2-eq/kg H2 which can be considered a wide range. The maximum absolute difference between the original and harmonized GWP results of a study is 1.5 kg CO2-eq/kg H2. Yet even the highest GWP of this study is over four times lower than the GWP of grid-powered electrolysis in Germany. Due to the lack of transparency of most LCAs included in this review, full identification of the sources of discrepancies (methods applied, assumed production conditions) is not possible. Overall it can be concluded that the environmental impact of the electrolytic hydrogen production process is mainly caused by the GWP of the electricity supply. For future environmental impact studies on hydrogen production systems, it is highly recommended to 1) divide the whole system into well-defined subsystems using compression as the final stage of the LCA and 2) to provide energy inputs/GWP results for the different subsystems

Integration of solar energy systems for increased societal support

How can we integrate photovoltaic (PV) solar energy systems in the built environment and rural landscapes while increasing societal support and making effective use of space? This important research question is inspired by several grand societal challenges, namely humankind’s response to anthropogenic causes of climate change, the required sustainable energy transition and innovations in the design of systems, products, buildings and local infrastructures which enable an optimal use of solar energy. Consequently, new sustainable energy environments must be created which will meet the needs of users, will fit in a societal context, will have an excellent performance in energy production and which will be aesthetically appealing. For this purpose a new interdisciplinary Dutch research consortium has been established, which will evaluate so-called ‘Solar Integration’ from the perspectives of (1) public acceptance, law and governance, (2) biodiversity, ecosystems and spatial quality, (3) PV system configurations in rural and urban landscapes, (4) enabling technologies for integrated PV elements, and (5) design approaches. This research consortium will support Solar Integration by (a) design-driven research on innovations in PV solar energy, (b) the creation of a broad consortium of stakeholders with various backgrounds and interests, (c) execution of the project in both the Netherlands and internationally, and (d) involving adult and young citizens in knowledge utilization

Washing with the Sun:Two residential smart grid pilots in The Netherlands

This paper presents a quantitative data analysis of smart wet appliances in two residential smart grids. The energy consumption patterns and flexibility of 175 smart washing machines and 9 smart dishwashers’ data were analyzed for the whole year (5 min. resolution, monitoring fraction > 90%) on two Dutch smart grid pilots; Jouw Energy Moment (JEM) 2014 and PowerMatching City (PMC) 2012. The research results show annual use of 540 hours of wet appliances for an average household. Besides, 770 hours of flexibility are realized annually thanks to users’ active participation and the energy management systems that were employed. In conclusion, energy demand could be identified as self-consumption for almost half of the smart appliances’ consumption in both pilots (PMC: 47%, JEM: 45%), showing a noticeable consumption shifted towards solar self-consumption

Designing innovative solutions for PV-powered electric mobility applications

Designing with photovoltaics is the core focus of this paper which presents the results of a design study on conceptual PV applications for electric mobility systems. This is a relevant direction for new product development because PV technology can contribute to improved features of electric mobility systems not just in terms of CO2 emissions reduction but also regarding product aesthetics and user experiences. Design studies are multidisciplinary by nature, therefore in this case technical, user, regulatory and aesthetic aspects are covered. Eleven conceptual designs were developed in 2019 by means of a design project executed at the University of Twente, encompassing solutions for PV-powered charging of electric vehicles, vehicle-integrated PV products and other applications. The concepts focus on various modes of transport beyond passenger cars such as public transportation, electric bicycles and utility vehicles, in some cases applying alternative charging technologies such as battery swapping and induction charging in their design. In this paper four of these conceptual designs are presented as case studies, showing their multidisciplinary focus as well as parts of the design process behind their development. An evaluation of these conceptual designs revealed several design challenges that need to be addressed in their development, including the limited space available for integrating PV cells, the technical limitations posed by some of the proposed charging methods and the effective visual communication of the concept’s intended function

PV DC Yield Determined by Deep Neural Networks:the Case of Building Integrated PV

PV systems can significantly contribute to achieving the climate neutral goal of the Paris agreement. However, they will present additional challenges to the power grids, due to their intermittent nature. This study aims to model the power output of Building Integrated PV systems (BIPV) on the basis of the application of a Deep Neural Network (DNN) to the following input variables: solar irradiance, module temperature as well as time and location. The DNN has been applied to a dataset containing over four years of data of electrical parameters on module level as well as meteorological data, all at a 5-minutes resolution. The results show that the proposed DNN is able to calculate the PV power output accurately with an R2 score of 0.96 and RMSE of 0.04. Though applied to a BIPV system in this case, the method will be applicable to a myriad of other types of monitored PV systems as well

Luminescent solar concentrator photovoltaics devices:Improving the power conversion efficiency by geometric design modifications

Luminescent solar concentrator (LSC) devices have been in development for nearly fifty years, usually aiming at enhanced combinations of luminophores and photovoltaic solar cells. In this research, the focus is on the development of new geometric designs of LSC PV devices to improve the performance. The research has been executed by LSC device ray-tracing simulation using software LightTools for LSC PV configurations with a PMMA lightguide doped with Lumogen Red 305 dye. The set of LSC models evaluated have different sizes, different dye concentrations and silicon PV cells on the backside and along all four edges. The simulation results show that with changes in size from 10 to 1,000 mm and dye concentration from 5 to 100 PPM, a 5 mm thick LSC planar light guide can have a total optical efficiency in the range of 77% to 90%. Moreover, a curved LSC lightguide with a dye concentration of 100 PPM also provides a good performance with provided 81% optical efficiency at the backside