Keep a Cooler Cold for Five Days

Ice melts because heat gets in, and it gets in three ways: through the walls, through the lid seal, and by walking straight in every time you open it. A cheap cooler managed well outlasts an expensive one managed badly, and the biggest single win costs nothing at all.

How to do it

1. Pre-chill the cooler

   A warm cooler eats a large share of your ice just getting itself cold. The night before, throw in a sacrificial bag of ice, or leave it in a cold garage. Dump that ice in the morning and load with fresh.

2. Freeze everything you can

   Meat, stock, chili, anything you are eating later in the trip goes in frozen and acts as ice. Frozen water bottles do double duty as drinking water as they melt.

3. Block ice on the bottom, cubed on top

   Block ice lasts far longer because it has less surface area. Cubed goes on top to fill gaps and chill fast. Air space is the enemy, so fill voids with towels if you have to.

4. Run a second cooler for drinks

   The drinks cooler gets opened twenty times a day and the food cooler gets opened twice. Separating them is the biggest gain most people are not using.

5. Keep it out of the sun and off hot ground

   Shade, and a towel or blanket over the top. Direct sun on a lid is brutal. On a truck bed, get it off the hot metal.

6. Leave the meltwater in

   Cold water holds cold better than air. Drain only when it starts floating your food, and pack meat in sealed bags so nothing gets waterlogged.

Where people go wrong

• Loading a warm cooler. You lose a day of ice immediately.
• Draining the meltwater every morning. You are pouring out your own cold.
• One cooler for everything. Every drink run dumps the cold air out.
• Leaving it in the sun with a dark lid. Shade and a cover are free.