Optimization of a Solar Photovoltaic Micro Grid for Electricity and Desalinated Water Production

Abstract

The sizing and operation of a renewable energy system to produce electricity and desalinated water for a self-sustained (isolated) community is presented and discussed in this paper. It is carried out using an algorithm based on ordinal optimization (OO) for sizing and dynamic programming (DP) for operation. DP is used to simulate and find the optimal operation strategy of the system for a given set of different system components’ sizes and loads. OO is an efficient method to search the design space and assess alternative designs and rank them initially using a simple model. The top-S designs are then identified and re-assessed using an accurate model to obtain a set of "good enough" solutions from which the best, with a given alignment probability, is identified. A system composed of a photo-voltaic (PV) generator, a battery storage system, a diesel generator, and a reverse osmosis system is proposed. Solar power being intermittent, a variable operation of the reverse osmosis system, in conjunction with a water storage tank, is proposed as a flexible load that can lead to higher energy efficiencies. Modeling of the power components is presented and the design results for different component prices and fuel costs are presented and discussed.