By Rabbi Yosef Braun, member of Badatz Crown Heights
One of the prominent poskim of the past generation, R’ Dov Berish Weidenfeld, who was the Tshebiner Rav and author of Dovev Meisharim, ruled that freezing water to make ice cubes on Shabbos is not permitted due to the prohibition of molid (creating a new entity), or nolad (benefitting from something that came into existence on Shabbos).
Other poskim argue that it might be similar to the melachah of boneh (using existing ingredients to construct something).
However, the majority of poskim rejected both these positions, and ruled that making ice cubes on Shabbos is permitted, provided they are intended for use on Shabbos.
In a case where there is a tzorech (need), there is even more room for leniency, as Shulchan Aruch tends to be lenient regarding similar aspects of nolad on Shabbos and Yom Tov if there is a tzorech.
Source: halacha2go.com
Rabbi Greenglass O”H, whom the Rebbe gave instructions to write a KITZUR HILCHOS DINIM, told me personally that it is permitted 100% to make ice cubes on Shabbos.
tzorech= if you have a guest and don’t have any cold drink
if any member of your family cannot drink warm water
you might be VERY chassidishe but don’t be frum (BEHIDUR) on somebody else
tzorech as in you don’t have any whereas non tzorech means you have already but there is cheshash that you may need more for shabbos (for a simcha) ect.
What exactly is the tzorech to have ice? Can’t drink coke without ice? Need ice in the vodka?
does that also include automatic icemakers built into the refrigerators
What about taking out ice on shabbos from an automatic ice maker? It refills itself when it senses that there isn’t enough ice?