It's all about energy

Perhaps you remember, or perhaps this will be a bit of a history lesson; an icebox used to literally be ice in a box. Before there were refrigerators powered by electricity to compress freon, there were iceboxes that would fit a huge chunk of ice and that would keep the refrigerator cool.

But where did the ice come from? Initially, it came from places that would freeze in the winter. There was a huge industry to cut ice off of lakes and move it around by horse and steam-powered ships to keep refrigerators cool.

If you didn't live at a time where it was happening, or if you aren't old enough to hear about it from those who lived during that time, it might sound a little crazy. We've come a long way since then.

And nowadays we can take advantage of the idea efficiently. There are grocery stores that get a salt solution down to very cold temperatures during the night when electric rates are low. Then they use the cold solution directly to keep their refrigerators cold during the day.

It's similar to the way battery banks have been set up in both commercial and consumer locations to charge at night and use battery power during the day when rates are high. And in a general way, this is used for refrigeration, too. The difference is that pumping a salt solution seems to be more efficient. Although there are some questions about how much the salt solution system requires to maintain.