Running a desalination plant intermittently would only make sense if the capital cost of building a plant is low compared to the electrical costs of operating i

Running a desalination plant intermittently would only make sense if the capital cost of building a plant is low compared to the electrical costs of operating it. My guess is they want to run those things 24 hours a day and store the water. Making smarter use of existing hot water heaters on the other hand is in some cases just a software upgrade or the installation of a smart controller.