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Motivated by a widely practiced strategy to combine the growth of the solar energy sector with poverty mitigation, we propose stylized models of households selling extra solar energy back to the grid, which generates a steady stream of income to overcome adoption barriers for solar panels, that is, high adoption cost and generation variability. By considering households' strategic consumption shifting behavior in response to varying intertemporal market electricity prices, we have presented the equilibrium adoption number and households' equilibrium profit. We have also demonstrated the government's optimal subsidy to reach a socially optimal adoption level. Furthermore, we investigate the popular Public Private Partnership (PPP) model in developing countries to promote the investment of solar panels. Under the PPP program, the private firms share both upfront cost and electricity revenue with households, while the government may provide subsidy to further encourage adoption. Despite the popularity of the PPP scheme, our model documents an unexpected negative implication by inducing a lower overall adoption level than the traditional scheme: As the PPP scheme relieves budgetary burden of households in adopting solar panels (infrastructure cost), anticipating the long‐term revenue loss, they are less likely to participate in the first place. However, combined with the government intervention via adoption subsidy, the PPP scheme can lead to a win‐win solution for all. [ABSTRACT FROM AUTHOR]

Problem definition: Many cities worldwide are embracing electric vehicle (EV) sharing as a flexible and sustainable means of urban transit. However, it remains challenging for the operators to charge the fleet because of limited or costly access to charging facilities. In this paper, we focus on answering the core question—how to charge the fleet to make EV sharing viable and profitable. Academic/practical relevance: Our work is motivated by the setback that struck San Diego, California, where car rental company car2go ceased its EV-sharing operations. We integrate charging infrastructure planning and vehicle repositioning operations that were often considered separately. More interestingly, our modeling emphasizes the operator-controlled charging operations and customers' EV-picking behavior, which are both central to EV sharing but were largely overlooked. Methodology: Supported by the real data of car2go, we develop a queuing network model that characterizes how customers endogenously pick EVs based on energy levels and how the operator implements a charging-up-to policy. The integrated queuing-location model leads to a nonlinear optimization program. We then propose both lower and upper bound formulations as mixed-integer second-order cone programs, which are computationally tractable and result in a small optimality gap when the fleet size is adequate. Results: We learn lessons from the setback of car2go in San Diego. We find that the viability of EV sharing can be enhanced by concentrating limited charger resources at selected locations. Charging EVs either in a proactive fashion or at the 40% recharge threshold (rather than car2go's policy of charging EVs only when their energy level drops below 20%) can boost the profit by more than 15%. Moreover, sufficient charger availability is crucial when collaborating with a public charger network. Increasing the charging power relieves the charger resource constraint, whereas extending per-charge range or adopting unmanned repositioning improves profitability. Finally, we discuss how EV sharing operations depend on the urban spatial structure, compared with conventional car sharing. Managerial implications: We demonstrate a data-verified and high-granularity modeling approach. Both the high-level planning guidelines and operational policies can be useful for practitioners. We also highlight the value of jointly managing demand fulfillment and EV charging. [ABSTRACT FROM AUTHOR]

Here we present a new method to treat cellulose with a sulfamic acid-urea-choline chloride (ternary deep eutectic solvent) system, which can realize both swelling and sulfation of cellulose. This can greatly reduce the energy consumption in the process of cellulose nanoization, and use it to successfully prepare food packaging films for eliminating odors. We hope that due its simplicity and resource-efficiency, this method will have a widespread influence on currently used (nano) cellulose modification protocols., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)