Paragraph On Thermal Heat Storage
Thermal Energy Storage is the temporary storage of high or low temperature energy for later use, bridging the gap between requirement and energy use. The storage cycle might be daily, weekly or seasonal depending on the system design requirements, and whilst the output will always be thermal, the input may be thermal or electrical.
1) Sensible Heat Storage
Heating a liquid or solid, without changing the phase: This method is called sensible heat storage. Temperature change depends on the amount of energy stored in the material can be expressed in the form. Energy is stored or extracted by heating or cooling a liquid or a solid, which does not change its phase during this process. A variety of substances have …show more content…
The amount of energy stored in this case depends upon the mass and latent heat of fusion of the material. In latent heat storage the principle is that when heat is applied to the material it changes its phase from solid to liquid by storing the heat as latent heat of fusion or from liquid to vapor as latent heat of vaporization. When the stored heat is extracted by the load, the material will again change its phase from liquid to solid or from vapor to liquid. The latent heat of transformation from one solid phase into another is …show more content…
Water then circulates through the pile during the day to produce chilled water that would normally be the chiller's daytime output.A partial storage system minimizes capital investment by running the chillers nearly 24 hours a day. At night, they produce ice for storage and during the day they chill water for the air conditioning system. Water circulating through the melting ice augments their production. Such a system usually runs in ice-making mode for 16 to 18 hours a day and in ice-melting mode for six hours a day. Capital expenditures are minimized because the chillers can be just 40 - 50% of the size needed for a conventional design. Ice storage sufficient to store half a day's rejected heat is usually adequate.A full storage system minimizes the cost of energy to run that system by entirely shutting off the chillers during peak load hours. The capital cost is higher, as such a system requires somewhat larger chillers than those from a partial storage system, and a larger ice storage system. Ice storage systems are inexpensive enough that full storage systems are often competitive with conventional air conditioning