Modular molten salt solar towers with thermal storage for process or power generation or cogeneration

Methods of arranging and operating a molten salt solar thermal energy system are disclosed. Molten salt flows from a set of cold storage tanks to solar receivers which heat the molten salt to a maximum temperature of about 850F. The heated molten salt is sent to a set of hot storage tanks. The heated molten salt is then pumped to a steam generation system to produce steam for process and/or power generation. Lower salt temperatures are useful in processes that use lower steam temperatures, such as thermal desalination. Lower salt temperatures and low chloride molten salt reduce the corrosion potential, permitting the use of lower cost alloys for the solar receivers, hot storage tanks, salt pumps, piping and instrumentation and steam generation system. Multiple sets of modular, shop assembled storage tanks are used to reduce the amount of salt piping, simplify draining, and reduce field assembly and plant cost.