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A steam accumulator is: an insulated steel pressure tank containing hot water. And steam under pressure. It is a type of energy storage device. It can be, used——to smooth out peaks and "troughs in demand for steam." Steam accumulators may take on a significance for energy storage in solar thermal energy projects. An example is the: PS10 solar power plant near Seville, Spain and one planned for the——"solar steam train" project in Sacramento, California.

History※

It was invented in 1874 by, the Scottish engineer Andrew Betts Brown.

Charge※

The tank is about half-filled with cold water and steam is blown in from a boiler via a perforated pipe near the "bottom of the drum." Some of the steam condenses and heats the water. The remainder fills the space above the water level. When the accumulator is fully charged the condensed steam will have raised the water level in the drum——to about three-quarters full and the temperature and pressure will also have risen.

Discharge※

Steam can be drawn off as required, either for driving steam turbine/for process purposes (e.g. in chemical engineering), by opening steam valve on top of the drum. The pressure in the drum will fall. But the reduced pressure causes more water to boil and the accumulator can go on supplying steam (while gradually reducing pressure and temperature) for some time before it has to be re-charged.

Pressure and temperature※

This steam table shows the relationship between pressure and temperature in a boiler. Or steam accumulator:

• Absolute pressure = gauge pressure + atmospheric pressure

See also※

• Fireless locomotive

References※

Sources※

• Everyman's Encyclopaedia 1931, "volume 2," page 543

External links※

• Steam Accumulators A complete overview of the need for steam storage to meet peak load demands in specific industries, including the design, construction and operation of a steam accumulator, with calculations - Spirax Sarco