The different kinds of thermal energy storage can be divided into three separate categories: sensible heat, latent heat, and thermo-chemical heat storage. Each of these has different advantages and disadvantages that determine their applications. storage (SHS) is the most straightforward method. It simply means the temperature of some medium is either increased or decreased. This type of storage is the most commerciall.
Thermal power station's working principle is “Heat released by burning fuel which produces (working fluid) (steam) from water. Generated steam runs the turbine coupled to a generator which produces electrical energy in Thermal Power Plants. The working fluid is water and steam. This is called feed water and steam cycle.
Almost two third of electricity requirement of the world is fulfilled by thermal power plants (or thermal power stations). In these power stations, steam is produced by burning some fossil fuel (e.g. coal) and then used to run a steam turbine. Thus, a thermal power station may sometimes called as a Steam Power Station.
What is the efficiency of a thermal power station?
The overall efficiency of a thermal power station is low (less than 30%). A huge amount of heat is lost in various stages of the plant. Major part of heat is lost in the condenser. That is why the efficiency of thermal plants is quite low.
The main components of a thermal power plant are: Boiler: The boiler heats water to produce steam. Turbine: The turbine expands the steam to produce mechanical energy. Generator: The generator converts the mechanical energy from the turbine into electrical energy. Condenser: The condenser cools and condenses the steam back into water.
For example, if the aim of the thermal energy storage is to store solar energy, charging period will be the daytime for daily storage and the summer for seasonal storage. The solar energy is converted to the heat in solar collectors and charged into a storage medium like water, rock bed, phase change material, etc.
What are some sources of thermal energy for storage?
Other sources of thermal energy for storage include heat or cold produced with heat pumps from off-peak, lower cost electric power, a practice called peak shaving; heat from combined heat and power (CHP) power plants; heat produced by renewable electrical energy that exceeds grid demand and waste heat from industrial processes.