I am starting a new discussion thread about how to power the Dexcom receiver when there is no electrical outlet available.
I am thinking about situations such as back country travel, Hurricaine Isabel (when we were without electricity for a week) and similar situations.
I spoke to Dexcom technical support and to the Dexcom trainer. They said that people had asked them about transformers for use in other countries. However they said that they had not heard a question about a situation when NO ELECTRICITY was available for more than 5 days.
Basically Dexcom does not know. They said that I should call Radio Shack. I asked for the number of watts that it draws so that I could specify this when looking at chargers. They referred me to page 127 of the manual but this does not have the wattage for the receiver. I looked all through the manual.
I was calling at 4:15 on Friday afternoon (Eastern Time) so the upper level supervisor had already left for the day.
I have noticed a new class of small portable solar chargers designed for cell phones, laptops and even for larger car and boat battery applications. Most all of the smaller units have USB outputs. Also I have purchased a New Trent external battery to extend use of my smart phone which can drain its battery within a day or so when using some applications. Google "solar power for laptops (cell phones)" for a range of options. A solar power device seems ideal for your problem.