Photovoltaic water pumping systems (PVWPS) are a promising solution to improve domestic water access in low-income rural areas. It is challenging, however, to make them more affordable for the local communities. We develop here a comparative methodology to assess relevant features of both widely employed PVWPS architecture with water tank storage, and hardly used PVWPS architecture with a battery bank instead of tank storage. The quantitative comparison is carried out through techno-economic optimization, with the goal of minimizing the life cycle cost of PVWPS with constraints on the satisfaction of the water demand of local inhabitants and on the groundwater resource sustainability. It is aimed to support decision-makers in selecting most appropriate storage for domestic water supply projects. We applied the methodology in the rural village of Gogma, Burkina Faso. Results indicate that the life-cycle cost of an optimized PVWPS with batteries is $24.1k while it is $31.1k if a tank is used instead. Moreover, reduced impact on groundwater resources and greater modularity to adapt to evolving water demand is noted if using batteries. However, as batteries must be replaced regularly and recycled adequately, PVWPS’ financial accessibility could increase only if sustainable and efficient operation, maintenance, and recycling facilities for batteries were present or developed locally.

Greenhouse gas emissions are one of the most critical worldwide concerns, and multiple efforts are being proposed to reduce these emissions. Shipping represents around 2% of global CO ${}_2$ emissions. Since ship power systems have a high dependence on fossil fuels, hybrid systems using diesel generators and batteries are becoming an interesting solution to reduce CO ${}_2$ emissions. In this article, we analyze the potential implementation of Li-ion batteries in a platform supply vessel system through simulations using HOMER software (Hybrid Optimization Model for Multiple Energy Resources). We evaluate the impact of battery characteristics such as round trip efficiency, rated power, and energy capacity. We also evaluate the potential CO ${}_2$ emissions reduction that could be achieved with two of the most common types of Li-ion batteries (lithium titanate, lithium iron phosphate). Furthermore, we consider that the Li-ion batteries are installed in a 20 ft container. Results indicate that the lithium iron phosphate battery has a better performance, even though the difference between both technologies is lower than 1% of total emissions. We also analyze the potential emissions reduction for different parts of a mission to an offshore platform for different configurations of the ship power system. The most significant potential CO ${}_2$ emissions reduction among the analyzed cases is 8.7% of the total emissions, and it is achieved by the configuration including the main and auxiliary diesel engines as well as batteries. Finally, we present managerial implications of these results for both companies operating ships and ship building companies.

A sensitivity analysis is carried out on the parameters of a photovoltaic water pumping system (PVWPS) for domestic water supply in rural areas. The results show that the photovoltaic modules peak power, the motor-pump efficiency, and the water tank volume strongly influence the system performance. This highlights that these parameters constitute judicious optimization variables. Besides, the cost of the motor-pump, the cost of the water tank, and the lifetime of the PVWPS have the largest impact on the system cost. These six parameters are therefore of primary importance for the technoeconomic optimal sizing of the system. Finally, it is shown that the hydraulic losses play a minor role and that it is not necessary to consider the evolution of the ambient temperature when modeling PVWPS for domestic water supply. This study can be useful to nongovernmental organizations, companies, and governments which install PVWPS for domestic water access. It can help them to determine the accuracy at which a given parameter has to be known to correctly model or size these systems. Besides, it can allow them to evaluate the robustness of PVWPS sizing to parameters variation with time and may guide their choice of components.