Desalination using reverse osmosis is just 6kwh/m3. It means 67 cubic km of water per year. Which is about as much water withdrawal as all of Russia. They can't possibly practically use that much water. It will be 10% of India's (world top), or 14% of U.S.' water use.

Does that include the energy used to pump the water after processing?

From what I understand the most energy-intensive part of desalination is pumping it to where people can actually use it.

They don't need to use it all for water. Electricity can be sold. Can also produce hydrogen and sell that.