I love dry ice. I use it in the "food cooler", which only gets opened four or five times a day, max. Any CO2 leakage is pretty darn insignificant compared to what gets constantly pumped out of the lungs of two adult humans, and does not constitute any meaningful safety hazard IMO. I'm able to keep the food cold for four days in an ordinary, 40 quart Igloo cooler. The trick is how much insulation (and what kind) to put between the dry ice and the food. If you don't use enough insulation it will freeze the food solid, and then when you remove the food to thaw it, you are removing a ton of thermal energy from the cooler and wasting it.
Obviously a certain level of discipline is required. Every time you open the cooler you are burning up precious energy. Opening the cooler and staring into it whilst daydreaming about kittens and ponies and hair care products must, and shall, result in a flogging. Or at least a spanking.
As far as a DIY icebox goes, I would consider building one out of styrofoam boards rather than wood, then covering it with fiberglass. You could make it any shape and size so it would fit wherever you wanted it to go; you could install drain holes, ventilation fittings, an airtight lid, even LED lighting? It would be cheap, sturdy, lightweight and (I would think) have excellent R value compared to most coolers.
Obviously a certain level of discipline is required. Every time you open the cooler you are burning up precious energy. Opening the cooler and staring into it whilst daydreaming about kittens and ponies and hair care products must, and shall, result in a flogging. Or at least a spanking.
As far as a DIY icebox goes, I would consider building one out of styrofoam boards rather than wood, then covering it with fiberglass. You could make it any shape and size so it would fit wherever you wanted it to go; you could install drain holes, ventilation fittings, an airtight lid, even LED lighting? It would be cheap, sturdy, lightweight and (I would think) have excellent R value compared to most coolers.
