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A common nonionic surfactant, Triton X-100, was used to modify the chemical bath deposition of CdS “buffer” layers on Cu(In,Ga)Se2 (CIGS) thin films. Addition of the surfactant to the CdS deposition bath allowed increased wetting of Cu(In,Ga)Se2 substrates and an increase in the uniformity of films, especially on model hydrophobic substrates. X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy data demonstrate that films produced with the surfactant have the same chemical and electronic properties as films grown without it. In CdS∕Cu(In,Ga)Se2 devices, it was found that Triton X-100 allowed the use of CdS layers that were three to four times thinner than those used normally in high efficiency CIGS-based devices and eliminated the large drops in open-circuit voltage that usually accompany very thin buffer layers. For these thin CdS layers and relative to devices made without the surfactant, average absolute cell efficiencies were increased from 10.5% to 14.8% or by a relative 41%. Visual inspection of the CdS depositions reveals one possible mechanism of the surfactant’s effects: Bubbles that form and adhere to the CIGS surface during the chemical bath deposition are almost completely eliminated with the addition of the TX-100. Thus, junction nonuniformities, pinholes, and thin areas in the CdS layer caused by poor wetting of the substrate surface are sharply reduced, leading to large increases in the open-circuit voltage in devices produced with the surfactant.

Solar energy is a natural source that provides clean and renewable energy, which supplies two types of energy: thermal energy and photovoltaic energy. Whereas, the most effective way to exploit this energy is photovoltaic cells. However, for all the incident solar radiation, the solar panels can absorb a limited quantity of energy. While, the rest of radiation energy gets lost as heat, that increases the temperature of the photovoltaic cells, this is the reason why the productivity of electricity is decreased. Therefore, to exceed this issue and benefit from the two sources of sun radiation, a hybrid thermo-electrical system is proposed. The system is a solar panel surrounded by the phase change material that can absorb the temperature to increase the efficiency of solar system and use this energy to produce a hot water.

Building‐integrated photovoltaics (BIPVs) stand as a promising solution to provide renewable electricity for achieving zero‐energy buildings, although still hindered from large‐scale implementations due to the difficulty of traditional photovoltaic modules in meeting the standards and aesthetics of architectural materials. The emergence of new photovoltaic materials and devices could pave the way for the future through offering diversity and tunability in colors and transparency along with comparable performance. Herein the recent advances in BIPVs are discussed, starting from an overview of various photovoltaic technologies regarding their material characteristics, state of the art, and adaptability to the built environment. The transparent and colored photovoltaic technologies are then respectively emphasized, concerning design principles, theoretical analysis, technical routes, and corresponding demonstration studies. The various strategies, including the materials and structures adopted to modify the transparency and color of solar cells, are highlighted. Finally, the challenges and future perspectives are addressed, followed by an outlook on factors that are critical for large‐scale implementation of BIPVs in the future.

The optical characteristics of a radially symmetrical core-shell spherical (CSSP) lens is analyzed for its suitability to application in microtracking concentrator photovoltaic systems (MTCPVs). The CSSP lens is compared to a conventional homogenous spherical lens through both ray-tracing simulations and outdoor experiments. Simulation results show that the CSSP lens is superior to the conventional homogenous spherical lens in terms of its optical efficiency for long focal lengths, for which the CSSP lens exhibits less spherical and chromatic aberrations. Outdoor experiments are conducted using test concentrator photovoltaic (CPV) modules with prototype CSSP and homogenous spherical lenses; the trend of the measured short circuit current agrees with the that of the simulated optical efficiency for both lenses. Furthermore, compared to the homogenous lens, the CSSP lens significantly increases module efficiency because of its better illumination uniformity at the solar cell surface. The optical characteristics of the CSSP lens are preferable for MTCPVs with a spherical lens array to achieve a higher module efficiency for a wider incidence angle although further studies on more practical system configurations are needed.

This paper aims to demonstrate the viability of energy harvesting for wide area wireless sensing systems based on dye-sensitized solar cells (DSSCs) under diffuse sunlight conditions, proving the feasibility of deploying autonomous sensor nodes even under unfavorable outdoor scenarios, such as during cloudy days, in the proximity of tall buildings, among the trees in a forest and during winter days in general. A flexible thin-film module and a glass thin-film module, both featuring an area smaller than an A4 sheet of paper, were initially characterized in diffuse solar light. Afterward, the protype sensor nodes were tested in a laboratory in two different working conditions, emulating outdoor sunlight in unfavorable lighting and weather to reconstruct a worst-case scenario. A Li-Po battery was employed as a power reserve for a long-range wide area network (LoRaWAN)-based sensor node that transmitted data every 8 h and every hour. To this end, an RFM95x LoRa module was used, while the node energy management was attained by exploiting a nano-power boost charger buck converter integrated circuit conceived for the nano-power harvesting from the light source and the managing of the battery charge and protection. A positive charge balance was demonstrated by monitoring the battery trend along two series of 6 and 9 days, thus allowing us to affirm that the system’s permanent energy self-sufficiency was guaranteed even in the worst-case lighting and weather scenario.

Depleting conventional energy resources are forcing the world to search for new and renewable energy resources. Solar energy is one of the potent and abundant energy resource .To use the solar energy to its fullest along with conventional technology has specific limitations. These limitations can be eliminated by use of Dye Sensitized Solar Cell (DSSC). DSSC can be seen as promising future technology. It is advantageous over Silicon (Si) based Photovoltaic (PV) cell in terms cost, easy manufacturing, stability at higher temperature, aesthetics, etc. Also it works in indoor conditions i.e. diffused sunlight which nearly not feasible with conventional PV cells. Now Research and Development Departments of many countries like Japan, Germany, USA, Switzerland, India, China and many firms like G-Cell, Oxford PV, Sony, TATA-Dyesol are working on DSSC to improve its various aspects so as to make it more applicable in various conditions. The paper will discuss the concept, construction, working of DSSC. Also it will illustrate current applications of DSSC.