Horsekeeping
The best way to keep drinks cold is good old-fashioned solid water.
We used to put our drinks in the refrigerator the night before and then use rechargeable freezer packs. This meant being organized enough to remember the drinks the night before and having enough room in the fridge. More importantly, this kept the drinks cool, but not cold.
Now, we fill the cooler with drinks, then dump one or two bags of party ice from the nearest gas station/convenience store. If it is a one-day show, we stop with Milton or do an ice run before we load. If it is a multi-day show, ice is our first order of business in the morning.
It’s not logistically convenient to buy ice each time, the semi-melted ice can be a pain afterwards, and we have had trouble with the cheap can’t-bring-ourselves-to-buy-a-Yeti cooler sweating all over everything.
However.
Having ice-cold drinks to hand has made all the difference in surviving sweltering summer horse shows.
Thank you for reading,
Katherine Walcott
Virtual Brush Box 
At one of those sweltering summer events you and Kathie introduced me to Gatorade. Thank you.
I’ve seen the plug-ins. Amazing. They save time, hassle and, eventually, money.
As a wise woman once said to me: most problems can be solved my throwing money at them.
Q: would it stay cold all day without being plugged in?
Much more comfort, much less work. Go for it!
If you plug it in to your car battery, wouldn’t you be draining the battery?
@debandtoby. Great stuff. The original green is a staple for us. I don’t see the point of all the different styles. It’s not like you drink Gatorade for the flavor. At least they stopped the G2 nonsense.
@Joan & debandtoby. Electricity is too hard to come by, even on showgrounds. Yetis are free-standing, well-made, well-insulated, and $$$.