eroei the quintessence of "economics"

ScienceDaily | The worst recessions of the last 65 years were preceded by declines in energy quality for oil, natural gas, and coal. Energy quality is plotted using the energy intensity ratio (EIR) for each fuel. Recessions are indicated by gray bars. In layman's terms, EIR measures how much profit is obtained by energy consumers relative to energy producers.The higher the EIR, the more economic value consumers (including businesses, governments and people) get from their energy. An overlooked cause of the economic recession in the U.S. is a decade long decline in the quality of the nation's energy supply, often measured as the amount of energy we get out for a given energy input, says energy expert Carey King of The University of Texas at Austin.

Many economists have pointed to a bursting real estate bubble as the initial trigger for the current recession, which in turn caused global investments in U.S. real estate to turn sour and drag down the global economy. King suggests the real estate bubble burst because individuals were forced to pay a higher and higher percentage of their income for energy -- including electricity, gasoline and heating oil -- leaving less money for their home mortgages.

In economic terms, the quality of the nation's energy supply is referred to as Energy Return on Energy Investment (EROI). For example, if an oil company uses a 10th of a barrel of oil to drill, pump, transport and refine one barrel of oil, the EROI for the refined fuel is 10.

"Many economists don't think of energy as being a limiting factor to economic growth," says King, a research associate in the university's Center for International Energy and Environmental Policy. "They think continual improvements in technology and efficiency have completely decoupled the two factors. My research is part of a growing body of evidence that says that's just not true. Energy still plays a big role."