
If your iPhone were powered by... - mizzao
http://graphics.wsj.com/iphone-battery/
======
gene-h
of course, they are completely ignoring the conversion efficiency of the fuel
sources to electricity.

Let's take diesel for instance, conversion efficiency of chemical energy to
work for small engines can be about 30% at best, so a much more reasonable
estimate for regular use is about 2.85 days rather than 9.5.

Now the interesting thing is that people have actually proposed using internal
combustion engines and fuel as a replacement for batteries in electronic
gadgets. to do so one uses tiny turbines micromachined using the same
techniques to make microchips. One researcher working on this technology
estimates that at max an energy density of 1500 Wh/l could be achieved, which
gets us a whopping 1.33 days of run time at regular use!
[http://thefutureofthings.com/3063-engine-on-a-
chip/](http://thefutureofthings.com/3063-engine-on-a-chip/)

~~~
arcticbull
Looks like Diesel engines have a thermal efficiency of up to 51.7% [1] (with a
theoretical maximum of 56% [2], and Toyota claiming a practical 38% [3]) and
Gasoline engines ~25%. Based on that, a Diesel powered phone would last
3.8-5.6 days.

[1]
[https://en.wikipedia.org/wiki/Thermal_efficiency](https://en.wikipedia.org/wiki/Thermal_efficiency)

[2] [http://hyperphysics.phy-
astr.gsu.edu/hbase/thermo/diesel.htm...](http://hyperphysics.phy-
astr.gsu.edu/hbase/thermo/diesel.html)

[3] [http://www.greencarreports.com/news/1091436_toyota-
gasoline-...](http://www.greencarreports.com/news/1091436_toyota-gasoline-
engine-achieves-thermal-efficiency-of-38-percent)

------
fasteo
>>> An iPhone powered by body fat could last...9 days

This only shows how extremely efficient our body is. We can survive without
food - with water though - for maybe 40-60 days depending how much fat you
carry.

~~~
SixSigma
Your body is radiating 1kw too.

~~~
thecabinet
More like 100W: 2000 Calories is 2000000 calories is 8,400,000 Joules. Divided
by a day is 97W.

~~~
SixSigma
Oops. My fallible memory

------
RizlaPleaseLa
What about uranium?

~~~
nacs
And antimatter.

------
SixSigma
Tbh there is no Moore's law for anything in the way it is implied in the
paragraph.

