Cooking outdoors is a source of great debates – the opinions are many, probably as many as there are backpackers, but there is a simple tool that most will agree upon: the use of a stove cozy. It is a small and light tool that does nothing but increase the efficiency of your pot and can be bought from a variety of companies, but can also be made easily at home. How does a cozy really help?
Backpacking pots are usually aimed at being as light as possible, made from the thinnest of metals such as titanium, aluminum and others. Being so thin means pots are light, durable and very fast to transfer heat, but they also cool down very fast. Extremely efficient stoves (lots to learn here, at Zen Stoves) when outdoors is great, but the fact that pots cool down so quickly means we lose all the heat we so effectively created. The fast loss of heat from thin pots results in either the need to use the hot liquid (or meal) straight away or deal with the fact that it will get cold very quickly. When backpacking in winter conditions, this is an ever bigger issue as the heat loss is so quick that there is a good chance only the start of your meal will be hot, losing all the positive effects of eating a hot meal. Another issue that results from the heat loss is that we need to carry more fuel to make sure we have hot food or liquids. If we continuously bring liquids to a boil there is a high cost of fuel; also, if you are simmering food, having a thin pot means a longer simmer.
Cozy to increase efficiency
Based on the limitation of a lightweight backpacking pot, we want to find a way to increase the efficiency without the “cost” of heavier pots, as a heavy pot might retain heat better (but will take longer to heat, so more fuel) and will keep our pot’s contents hot for longer. The best way to increase the pot’s efficiency is by increasing the insulation level of the pot while trying to reduce the weight using the best insulation tools: air and reflective materials. Air is nature’s best insulator, so finding the right way to trap it is crucial – though not simple when making your own cozy. The best “air trapper” is goose down, but making a down cozy would be amazingly expensive and too sensitive. We want a simpler and cheaper way – maybe bubble wrap? Bubble wrap is very effective but too sensitive, so we need a stronger material than the average nylon, something metal-based or a strong plastic (that won’t melt).
Another good way to get increased heat retention is to turn the pot’s heat on itself using a heat reflection material, such as tin foil or the like. Reflective plastic has been used for a while now as a cheap and light tool to create heat retention. The best material (and cheapest) to get those two features is using a windshield sun shade for your DIY cozy – they are made from robust reflective material that has air bubbles to insulate the car’s interior on sunny days. We can use the windshield sun shade to create an insulating sleeve that can be fitted on the pot after the boil to retain the heat of the pot’s contents. Liquids will hold heat longer, simmering time will be shorter, and food (while eating/preparing) will stay hot for longer.
Making the Cozy
What you need:
The pot that will be housed in the cozy Pen Scissors Duct tape Windshield sun shade
Step by step guide:
- Mark the shape of the bottom of the pot and the lid on the shade
- Cut the shapes out
3. Mark a strip of shade to the height of the pot + 2mm
4. Cut the strip
5. Wrap the strip around the pot and cut off the excess material
6. Tape the edges of the strip to make a loose sleeve around the pot
7. Fit the bottom shape into the sleeve and secure on the inside using duct tape
8. Tape the bottom of the cozy all around on the outside (tip: cut the tape in a “sun” formation for easy taping)
9. Tape the inside of the cozy using small tape strips
10. Cut a hole in the middle of the lid shaped shade in a rectangular shape
11. Tape the edges of the lid shade on the rectangular to secure it
12. Cozy is ready! Fit the pot in the sleeve and the lid handle through the “slit” in the lid
Final words and how to use
This cozy is so easy to make and is using the simplest shade I could find (£3.99 on Amazon) and duct tape that I always have at home,
resulting in 26g of extra insulation for my new Solo Stove. I plan on trying out the cozy soon, and may even make one for my MSR Reactor. The best use for a cozy depends on what kind of food you usually eat outdoors;
- Cook your own – if you need to just cook your food using simmering (rice, couscous etc), place your pot with your food in the cozy a few minutes before the end of the cooking process to let the cozy do the final cooking and not your stove, saving fuel.
- Using freeze dried meals – these meals tend to be cooked in the bag they come in – you just add water to the bag and the food rehydrates in the bag, no need for a pot. To increase the efficiency and make sure you always eat really hot food, pour the water in the bag, take the pot off the heat and into the cozy, place the bag in the pot to rehydrate. Your food will stay warmer during the re-hydration stage of the meal.
Don’t fear the idea of MYOG (Make Your Own gear) and give it a first attempt with the simple cozy to increase your backpacking food experience.