In 2010, the world produced a staggering 324,181,889 tonnes of potatoes. They are the world’s number one non-grain crop, in 130 countries, and a hefty source of starch for billions around the world. They are cheap, store easily, and last for a long time. So think to yourself, why cant i run my pc on it, well you can, just follow my step by step potato pc build guide. But first you need to know a few things.

The humble potato can output about ~1.6 volts and 2 milliamps
(0.0002 amps) with this we can figure out how many potatos we need, but we also need a sytem, here are the specs.
- Raspberry PI 3 Model B A1.2GHz 64-bit quad-core ARMv8 CPU, 1GB RAM
($59.99) on amazon.com
- TFT Touch Screen, Kuman 3.5 inch 320x480 Resolution TFT LCD Display with Protective Case + 3 x Heat sinks+ Touch Pen for Raspberry Pi 3 Model B, Pi 2 Model B & Pi Model B+ SC11
($30.99) on amazon.com
- iPazzPort Wireless Mini Handheld Keyboard with Touchpad Mouse Combo for Android TV Box and Raspberry Pi 3 and HTPC and XBMC KP-810-19S - Black
($22.99) on amazon.com
- Transcend 2 GB SD Flash Memory Card (TS2GSDC)
($6.99) on amazon

this system will require 15 watts of power on max load. the equation
Watts = Amps x Volts will show us how many watts out potato will produce
Watts = 1.6 * 0.0002
Watts = 0.00032 per potato
now we divide 15 by 0.00032 to find the amout of potatos requred.
we find we need 46,875 potatos, to run a true potato computer.