H. Kakiuchi et al., Development of new PCM using sodium acetate trihydrate and characteristic evaluation of capsule type heat storage system, KAG KOG RON, 27(1), 2001, pp. 7-14
We attempted to design a capsule type heat storage system, which can store
heat with warm water 333 K and can produce warm water lover 320 Ii directly
from the heat storage tank. We developed a new PCM with melting point 323
K and heat of fusion 205 kJ/kg. This PCM was obtained by adding sodium nitr
ate to sodium acetate trihydrate. It is found that this PCM melted with war
m mater of 333 K and crystallized at 321 K. Also, it was found that heat qu
antity and melting point of this PCM didn't change even if freezing and mel
ting was repeated 1,100 times.
We carried out characteristics evaluation of this system. It was found that
this system could store heat with warm water (333 K) within 10 hours. So,
this system is able to use off peak discount electric power. The theoretica
l heat storage quantity of this system is 322 MJ and the experimental value
was 305 MJ in this evaluation. So, it is understood that this system could
store heat almost equal to the theoretical value. Also, it was found that
this system could produce warm water over 320 K, which is required space he
ating, and can release almost stored heat.