A large portion of life cycle transportation impacts occur during vehicle operation, and key improvement strategies include increasing powertrain efficiency, vehicle electrification, and lightweighting vehicles by reducing their mass. The potential energy benefits of vehicle lightweighting are large, given that 29.5 EJ was used in all modes of U.S. transportation in 2016, and roughly half of the energy spent in wheeled transportation and the majority of energy spent in aircraft is used to move vehicle mass. We collect and review previous work on lightweighting, identify key parameters affecting vehicle environmental performance (e.g., vehicle mode, fuel type, material type, and recyclability), and propose a set of 10 principles, with examples, to guide environmental improvement of vehicle systems through lightweighting. These principles, based on a life cycle perspective and taken as a set, allow a wide range of stakeholders (designers, policy-makers, and vehicle manufacturers and their material and component suppliers) to evaluate the trade-offs inherent in these complex systems. This set of principles can be used to evaluate trade-offs between impact categories and to help avoid shifting of burdens to other life cycle phases in the process of improving use-phase environmental performance.

Light‐induced degradation (LID) is a well‐known problem faced by p‐type Czochralski (Cz) monocrystalline silicon (mono‐Si) wafer solar cells. In mono‐Si material, the physical mechanism has been traced to the formation of recombination active boron‐oxygen (B–O) complexes, which can be permanently deactivated through a regeneration process. In recent years, LID has also been identified to be a significant problem for multicrystalline silicon (multi‐Si) wafer solar cells, but the exact physical mechanism is still unknown. In this work, we study the effect of LID in two different solar cell structures, aluminium back‐surface‐field (Al‐BSF) and aluminium local back‐surface‐field (Al‐LBSF or PERC (passivated emitter and rear cell)) multi‐Si solar cells. The large‐area (156 mm × 156 mm) multi‐Si solar cells are light soaked under constant 1‐sun illumination at elevated temperatures of 90 °C. Our study shows that, in general, PERC multi‐Si solar cells degrade faster and to a greater extent than Al‐BSF multi‐Si solar cells. The total degradation and regeneration can occur within ∼320 hours for PERC cells and within ∼200 hours for Al‐BSF cells, which is much faster than the timescales previously reported for PERC cells. An important finding of this work is that Al‐BSF solar cells can also achieve almost complete regeneration, which has not been reported before. The maximum degradation in Al‐BSF cells is shown to reduce from 2% (relative) to an average of 1.5% (relative) with heavier phosphorus diffusion.

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All over the world, almost one billion people live in regions where water is scarce. It is also estimated that by 2035, almost 3.5 billion people will be experiencing water scarcity. Hence, there is a need for water based technologies. In separation processes, membrane based technologies have been a popular choice due to its advantages over other techniques. In recent decades, sustained research in the field of membrane technology has seen a remarkable surge in the development of membrane technology, particularly because of reduction of energy footprints and cost. One such development is the inclusion of nanoparticles in thin film composite membranes, commonly referred to as Thin Film Nanocomposite Membranes (TFN). This review covers the development, characteristics, advantages, and applications of TFN technology since its introduction in 2007 by Hoek. After a brief overview on the existing membrane technology, this review discusses TFN membranes. This discussion includes TFN membrane synthesis, characterization, and enhanced properties due to the incorporation of nanoparticles. An attempt is made to summarize the various nanoparticles used for preparing TFNs and the effects they have on membrane performance towards desalination. The improvement in membrane performance is generally observed in properties such as permeability, selectivity, chlorine stability, and antifouling. Subsequently, the application of TFNs in Reverse Osmosis (RO) alongside other desalination alternatives like Multiple Effect Flash evaporator and Multi-Stage Flash distillation is covered.