Freeze desalination via thermoacoustic cooling: System analysis and cost overview

Clean, drinkable water is essential for human health and well-being. However, access to clean water is becoming a global problem due to climate change and over exploitation of natural water resources. Desalination is widely accepted as a solution to meet water demands in areas with access to seawater. However, remote areas such as small islands far from the mainland pose a special challenge as they lack the infrastructure to meet electricity and water demands. This paper investigates the deployment of freeze desalination (FD) coupled with thermoacoustic engine and refrigerator (TAE/R) to provide freshwater to small settlements in remote locations like small islands. It presents an economic feasibility assessment of deployment of waste energy to satisfy the freshwater requirements, as an alternative to using conventional techniques such as reverse osmosis (RO) and thermal distillation (TD) that are energy intensive. Different scenarios are presented comparing the economic feasibility of FD vs. RO. The analysis is done based on the net present value (NPV), internal rate of return (IRR), selling price, and payback period using cashflow diagrams. Compared with the RO, FD powered by TAE/R turns out to be the most favorable option to produce freshwater from seawater for a small community on an isolated island due to high NPV and IRR, and low selling price and payback period.