A 15 yr old Canadian girl has invented a flash light that uses the temperature of the palm to light up. Ann Makosinski invented the flashlight that work in the principle of thermoelectric effect. Thermoelectric effect is the conversion of difference in temperature into electric voltages.
Everyone must have faced a moment or two where they would be searching for the flashlight to find something important and when they find the flash light they batteries would be dead. She said that this invention would save a lot of money and would lead to a reduction in toxins going into the soil if we don’t have to use batteries anymore.
For creating the flashlight she first measured the amount of electricity that can be generated from the warmth of the palm which came out to be 57 milliwatts and how much energy she needed to power the LED which would be around half a milliwatt. Next she got Peltier tiles which would generate electricity when one side is warm and the other is cool.
The light generated by her flashlight may not be powerful but is enough to find something or lighten up the page of a book. At an ambient temperature of about 10 degrees Celsius it worked for around half an hour but the working time will depend upon the difference in temperature.
Makosinski said that the model she has made is just a prototype of the final product she has in mind but the components she has used are quite strong and if it would be manufactured then she would surely seal off the electronic components of the light to save them from elements like water so that they can last longer.
She has submitted her invention to Google science fair and will visit the Google headquarters in California in September for the final event.