The Energy Return on Energy Invested (EROI or EROEI) is the amount of energy acquired from a particular energy source divided by the energy expended, or invested, in obtaining that energy. EROI is an essential and seemingly simple measure of the usable energy or "energy profit" from the exploitation of an energy source, but it is not so easy to determine all of the energy expenditures that should be included in the calculation. Because EROI values are generally low for renewable energy sources, differences in these estimates can lead to sharply divergent conclusions about the viability of...

According to the conventional wisdom, we live in a post-industrial information age. This book, however, paints a different picture: We live in the age of oil. Petroleum fuels and feedstocks are responsible for much of what we take for granted in modern society, from chemical products such as fertilizer and plastics, to the energy that moves people and goods in a global economy. Oil is a nearly perfect fuel: Energy dense, safe to store, easy to transport, and mostly environmentally benign. Most importantly, oil has been cheap and abundant during the past 150 years. In 1998, two respected...