Modeling Microwave Heating of Molten Salt for Thermal Storage Systems

Abstract

With the aim of affordably storing energy produced by photovoltaic and wind power plants, Power-to-heat-to-power (or Carnot batteries) are proposed as an outstanding system capable of transforming this energy into heat through existing commercial thermal storage systems for thermosolar plants, and again produce electricity by connecting these storage systems to available power blocks that can come from dismantled carbon plants or any other such as gas plants, or even nuclear. On this basis, microwave heating is studied as feasible to store energy in molten solar salt: 60%w NaNO3, 40%w KNO3. This study is expected to provide some key points for the design of microwave systems for molten solar salt, analysing different simulated cases with numerical modeling: continuous flow microwave heating in an elliptical cavity with different flow rates – 1 l/min and 1.6 l/min – and different positions of the fluid carrier tube, and in a microwave oven with helical tubes.