So i went ahead and manually checked for myself. For those interested:
100 Gas Cans = +75,000 EU
100 Peteoleum, 100 Gas Cans and 100 Mineral Oil = -60,000 EU
100 Mineral Oil to Gas converions = -25,000 EU and +75,000 EU
So,
150,000 EU - 85,000 EU = 65,000 EU
1 Gas can = 750 EU
Excess Gas = 65,000 EU / 750
Excess Gas = 86 Gas Cans.
This means 1 shuffle provides energy for itself and leaves excess of 86 cans. Good idea if you want to keep the Extraction/Refinery claim seperate.
Yours Truly,
The King of Time Wasting and Pointless Excercises.