Easy and Efficient Heat Source

One of the biggest challenges in the backcountry is staying warm in unfair conditions. I have found myself many times in extremely high winds or damp conditions that prevent me from building a fire. If you do not have a heat source available, the only heat you have is the heat your body is producing. One trick to providing extra heat throughout the night is to make a hot water bottle. The key is to create an insulator that will keep the water warm for hours. The only items you will need for this project I have listed below.

• Mylar Bubble Wrap (Can be purchased at any hardware store)
• Duck Tape
• The Water Bottle of Choice (I use a Nalgene Wide Mouth)
• Knife or Box Cutter

I will give a brief description about how I made this water bottle insulator and I will attach my YouTube video providing an overview.

1. You simply take two pieces of Mylar cut the same size to fit the water bottle with extra to fold at the bottom.
2. Then, place each piece with the foil facing outwards around the water bottle and wrap with duct tape.
3. Cut holes into the sides similar to the picture shown.

You’re done!

I have tested this using boiling water, placing into a stuff sack and hanging it outside at temperatures ranging from 42 to 51 degrees. I checked the bottle at 4 hours and the bottle was still substantially warm. The Mylar reflects the heat back into the bottle and the holes allow the heat to be forced out. This generates heat while allowing the bottle to maintain its warm temperature for hours. I use this in the foot part of my sleeping bag, at my side in the sleeping bag or hung by paracord at the end of my hammock so I can place my feet on it. This is just a simple way to provide supplemental heat for hours on those cold frigid nights.