Here is my styrofoam container:
I made the hole with a piece of hot wire.
With the Anova sitting on the lid, the bottom of the unit is about 5 mm from the bottom of the container, so there is no need to heat more water than necessary. Capacity is 13.5 litres (about 3.5 US gallons). I’ll add a small hole in the opposite corner so steam can escape somewhere other than around the Anova.
I’ve tested this with a gallon of boiling water. No issues with the styrofoam deforming or the like and, even after several minutes with (still near-boiling) water inside, the outside doesn’t even get warm to the touch.
Cost was zero because I received the box as part of a food delivery after ordering online.
I’ll keep an eye on it, thanks. I expect that it’ll last for at least a year or more. Not too bad for something that I had lying around anyway.
Heating time for 6.2 litres of water from 32 ºC to 75 ºC was 23 minutes, which is very close to the theoretical value at 0.8 kW: https://www.easycalculation.com/physics/thermodynamics/water-boiling-time-calculator.php
Heat loss is minimal, about 3.9 ºC per hour, from 75 ºC down to 71.1 ºC in a room at 25 ºC.
Nice! Good heat retention, and better still repurposing something on hand to get just what you need!
As Teledog says, keep an eye on it, i had a bit as packing, i poured boiling water on it and the bobbles did swell up, that said its a very good insulator. good luck
Just wondering if there is a good way of waterproofing the inside of these styrofoam boxes. I guess that a plastic bag would be OK; any other suggestions? My guess is that any paints may dissolve the styrofoam.
I use a styrofoam box but I also have a 15 litre plastic container inside it.
I didn’t bother waterproofing anything. The box holds water just fine, no problem.