We examined data on fuel consumption and costs for the years 1950 through 2013, along with economic and population data, to determine the percent of U.S. gross domestic product (GDP) spent each year on fuels, including fossil fuels and nuclear ore, and the growth of the economy. We found that...

In the last decade, the importance of exploiting Chile’s Renewable Energy Sources (RESs) has increased significantly, as fossil fuel prices have risen and concerns regarding climate change issues grown, posing an important threat to its economy. However, to date, the advancement of Renewable...

As an emerging country and one of the most populous countries in the world, Indonesia requires a sufficient energy supply to ensure the nation’s continued development. In response to this increasing energy demand, various studies have proposed energy-saving measures; building envelope design...

Energy Return on Investment (EROI) refers to how much energy is returned from one unit of energy invested in an energy-producing activity. It is a critical parameter for understanding and ranking different fuels. There were a number of studies on EROI three decades ago but relatively little work...

The main objective of this manuscript is to provide a formal methodology, structure, and nomenclature for EROI analysis that is both consistent, so that all EROI numbers across various processes can be compared, and also flexible, so that changes or additions to the universal formula can focus...

Declining energy return on investment (EROI) of a society’s available energy sources can lead to both crisis and opportunity for positive social change. The implications of declining EROI for human wellbeing are complex and open to interpretation. There are many reasons why frugal living and...

This paper is a synthesis of a series of twenty papers on the topic of EROI, or energy return on investment. EROI is simply the energy gained from an energy-obtaining effort divided by the energy used to get that energy. For example, one barrel of oil invested into getting oil out of the ground...

Oil has played a crucial role in the United States’ continued but increasingly tenuous economic prosperity. The continued availability of cheap, high energy return on investment (EROI) oil, however, is increasingly in doubt. If cheap oil is increasingly constrained, how might that impact the...

An inexact fuzzy multi-objective programming model (IFMOP) based on the environmental carrying capacity is provided for industrial structure optimization problems. In the IFMOP model, both fuzzy linear programming (FLP) and inexact linear programming (ILP) methods are introduced into a...

The rapidly growing world population and rising consumption of biofuels are increasing demand for both food and biofuels. This exaggerates both food and fuel shortages. Using food crops such as corn grain to produce ethanol raises major nutritional and ethical concerns. Nearly 60% of humans in...