Vegetables and herbs play a central role in the human diet due to their low fat and calory content and essential antioxidant, phytochemicals, and fiber. It is well known that the manipulation of light wavelengths illuminating the crops can enhance their growth rate and nutrient contents. To date, it has not been easy to generalize the effects of LED illumination because of the differences in the plant species investigated, the measured traits, the way wavelengths have been manipulated, and the plants’ growing environments. In order to address this gap, we undertook a quantitative review of LED manipulation in relation to plant traits, focusing on vegetables and herbs. Here, we use standardized measurements of biomass, antioxidant, and other quantitative characteristics together with the whole range of the photosynthetic photon flux density (PPFD). Overall, our review revealed support for the claims that the red and blue LED illumination is more reliable and efficient than full spectrum illumination and increases the plant’s biomass and nutritional value by enhancing the photosynthetic activity, antioxidant properties, phenolic, and flavonoids contents. Although LED illumination provides an efficient way to improve yield and modify plant properties, this study also highlights the broad range of responses among species, varieties traits, and the age of plant material.
With the sharp increase in global energy demand, industrial and residential buildings are responsible for around 40% of the energy consumed with most of this energy portion being generated by non-renewable sources, which significantly contribute to global warming and environmental hazards. The net-zero energy building (NZEB) concept attempts to solve the global warming issue, whereby a building will produce, on-site, its required energy demand throughout the year from renewable energy sources. This can be achieved by integrating photovoltaic (PV) building materials, called building-integrated photovoltaic (BIPV) modules, throughout the building skin, which simultaneously act as construction materials and energy generators. Currently, architects and builders are inclined to design a building using BIPV modules due to the limited colors available, namely, black or blue, which result in a monotonous building appearance. Therefore, there is an increasing demand/need to develop modern, aesthetically pleasing BIPV green energy products for the use of architects and the construction industry. This review article presents the current stage and future goal of advanced building integrated photovoltaic systems, focusing on the aesthetically appealing BIPV systems, and their applications towards overcoming global challenges and stepping forward to achieve a sustainable green energy building environment. Additionally, we present the summary and outlook for the future development of aesthetically appealing building integrated photovoltaic systems.
The building integrated photovoltaic (BIPV) system is one of the contributors which has enormous potential to reach the goal of net-zero energy buildings (NZEB) that significantly reduce the use of fossil fuels that contribute to global warming. However, the limitations of the visual and aesthetic appearance of current BIPV systems make this aspiration unlikely. This study investigates the limitations of the single-color-based PV modules that are dull in appearance and have low photo-conversion efficiency (PCE). In order to solve this issue, we designed, developed, and characterized micro-patterned-based multicolored photovoltaic (MPCPV) modules which are applicable to net-zero building and development. Our newly developed MPCPV module exhibits an aesthetically attractive and flexible building color suitable for industrial application. Furthermore, the MPCPV module possesses an efficiency of 9.6%, which is 4.1% higher than a single-color PV module (5.5%) but closer to conventional thin-film PV modules. In addition, the other output parameters, such as short-circuit current (Isc), open-circuit voltage (Voc), maximum power (Pmax), and fill factor (FF), indicate that our developed colored PV module is suitable for modern infrastructures that will enable energy generation on-site without compromising the aesthetic appearance. Finally, this research will have a substantial influence on the NZEB and will play an important part in the development of a sustainable environment.