Nowadays almost all big buildings use large, high energy consuming airconditioning units to keep their buildings at a reasonable temperature throughout the year. Especially in the summer these cost an enormous amount of energy.
This problem has lead to some very fine solutions lately to keep the temperature in buildings down, of which the melting and solidifying of salts is one of the coolest.
The two types of salts used in this test have melting points between 20-25 degrees Celsius, which means that whenever the temperature is below they will solidify, thereby sending out heat and when it’s above they will take up heat to be able to melt the salt.
The main problem right now is that it’s very hard to give a small spread to the salts. Currently the spread of about 3 degrees Kelvin is normal, but the hope is to bring it down to maximum one degree spread.
The good point already is that these salts are able to almost take away the entire cooling need for part of an ABN AMRO office, as the research by TNO has shown. All we can hope for now is that many more buildings will follow.