Experts who study this use the terms “net energy ratio” or “energy returned on energy invested” (EROEI).
Decades ago when the most accessible reserves were drilled, an oil company might produce 100 barrels of oil or more for each barrel’s worth of energy invested.
Declining oil field productivity has brought the average net energy ratio for conventional oil down to approximately 20:1 globally, with more remote or hard-to-refine oil significantly worse.
For fossil energy generally, the trend is downward despite technological advances in exploration and drilling. Some studies suggest that corn-derived ethanol actually has a negative net energy ratio—that is, more energy than a gallon of ethanol can deliver is used to produce a gallon of ethanol.
"The way those houses are all packed in there parties just spill out all over." Karolczyk JANESVILLE - Four Janesville men were stabbed during a fight outside bars in the city's downtown area early this morning, according to the Janesville Police Department.