Handwarmers and Climate Change

There are liquid fuel handwarmers, there are electronic handwarmers, there are chemical handwarmers, and variations and hybrids of all of these. There is no free lunch, no matter how your handwarmer produces heat, it needs an energy source.

The liquid fuel handwarmers convert fossil fuel to heat energy via a chemical process known as exothermic reaction. They evaporate Naptha.

The energy content value of naptha is about 20,700 BTU/lb
The energy content value of gasoline is 20,000 BTU/lb

A liquid fuel handwarmer will run for about 12 hours on 25 ml of naptha
The estimated fuel consumption of an idling engine is 0.6 litres / hr per litre of engine displacement. This means that an idling 3.5 litre engine consumes about the same amount of fuel in 45 seconds as your handwarmer does in 12 hours.

Want to grab a coffee or a quick meal? When the drive-through line is too long, consider heading to the take-out counter. This way, you won’t let your engine idle for more than 45 seconds.

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