A project to calculate CO2 emissions of mining bitcoin.
We wanted to understand how much energy was going into the computing the hashes in bitcoin and hence how much CO2 was being produced.
Generating electricity releases 500 grams of CO2/kWhe. Based on: wikipedia
The average efficiency of the bitcoin miners in the system is 2000 Mhash/J. Which is conservative. Source: mining hardware comparison
We have generated a function which fits the HashRate up to now - it assumes it's exponental.
According to our calculations as of May 1st 2014 each bitcoin will release ~103 kg of CO2 into the atmosphere. That happens once every 24 seconds.
If efficiency of bitcoin miners stays the same. That number will reach ~1602 kg of CO2 by May 1st 2015.
We've provided the code which is Wolfram Mathematica (version 9).