Fonctionnement - Vaccuum bottle

Fill the glass bottle with a hot or cold drink. Close the cap tightly and add the 'cup lid' on top.

To limit heat losses, the aluminium foil around the glass bottle reflects the heat rays inwards. The insulation reduces heat loss through conduction. The lid also limits heat loss and can be used as a drinking cup.

If the lid does not fit very well in place, attach it to the bottle with a wide elastic.

Although less effective than a vaccuum bottle, the insulated bottle of this project limts heat losses quite well and can keep a drink hot or cold for several hours.