Question1:Could this sweat-powered tattoo power our gadgets?
For 2 mornings in succession I have been subjected to what I can only describe is further what I call
I did work in the UK Power Generation Industry for some years and one of my take away nuggets is that many people have no idea how much energy they use per day, or the magnitude of energy differences used by their technology, nor how much energy the different power generation sources such as Solar, Wave, Wind, Coal, Nuclear actually produce.
So back to the first article
by Kelsey Campbell-Dollaghan
The article does say the electricity produced is about 70 microwatts per square centimetre of skin, which probably already lost most of the prospective audience.
With that as an exercise to the reader, and given the basic fact that 1 Watt is 1 Joule per second. Then how many Joules of Energy or Watts of Power do the following require or produce:
- A serious cyclist, sprinting on a straight road
- You Apple iPad or equivalent tablet, switched on and connected to Wifi
- An 80Kg man or woman performing a 10Km run
- Realisable energy from burning 1Kg Petrol in a car engine
- 30 minutes of a Cooker Oven being on at 200 deg C to make a modest dinner
- A dishwasher on a 90 minute, 50 degree C cycle
- A one metre square solar panel in direct sunlight
- The end to end Energy production cost of a one metre square solar panel including shipping, and recycling
- The power produced by a 300 BHP car engine
- The time in seconds to boil 100ml cup of water from room temperature at 20 degrees C using the Sweat Powered Tatoo.
70 microwatts is 70 x 10 -6 watts
100ml of water is 0.1 litres and 100 grams
So therefore the energy in Joules to heat 100 grams of water thru 1 degree = 4.186 * 100 = 418.6 Joules
So to raise by (100 - 20) = 80 degrees == 418.6 * 80 = 33488 Joules
1 Watt is 1 Joule per Second
so 70 x 10 -6 * <answer.seconds> = 33488
Time = 478, 400, 000 seconds
= 5537 days == 15 years
So based on the Sweat Technology it would take 15 years to boil 1, small cup of Water, say for a cup of coffee.
In summary: The next time somebody tells you that there is a revolutionary way to solve the worlds energy problems, please make a few calculations before applauding.