Application of solar-powered desalination in a remote town in South Australia

Abstract

Coober Pedy is a remote town in South Australia with abundant solar radiation and scarce and low quality water, where a reverse osmosis plant has been operating since 1967. This paper evaluates the feasibility of powering the plant with solar or photovoltaic (PV) panels whilst avoiding energy storage in batteries. Pilot tests were performed in October 2005 with a small scale PV-powered hybrid ultrafiltration-reverse osmosis (UF/RO) membrane filtration system. The performance of the system in Coober Pedy is presented over different operating conditions and two available brackish feed waters. The system has been shown to tolerate well the power variation during clear sky days due to direct use of PV panels, producing 764 L of water per solar day with average specific energy consumption of 3.2 kWh.m-3 when treating the groundwater with conductivity of 7.4 mS.cm-1. It has been concluded that a reverse osmosis plant utilising UF pre-treatment and powered by PV panels without battery storage is a promising alternative for Coober Pedy to overcome currently high energy costs for the existing RO plant.