Consumers often purchase more than one differentiated product, assembling a portfolio, which might potentially affect substitution patterns of demand and, as a consequence, oligopolistic firms’ pricing strategies. This paper studies such consumers’ portfolio considerations by developing a...

The two methods of processing synthetic crude from organic marlstone in demonstration or small-scale commercial status in the U.S. are <em>in situ</em> extraction and surface retorting. The considerable uncertainty surrounding the technological characterization, resource characterization, and choice of...

In China there has been considerable discussion of how one should express the efficiency of energy conversion and production. Energy return on investment (EROI) can be useful for this because its methodology is based on outputs and inputs. Unfortunately, similar to the rest of the world, most of...

The authors of this paper have been involved in contentious discussion of the EROI of biomass-based ethanol. This contention has undermined, in the minds of some, the utility of EROI for assessing fuels. This paper seeks to understand the reasons for the divergent results.

Promotion of undergraduate student thinking and learning in the realm of sustainable production is a new focus for horticulture curricula. In a writing intensive course, Greenhouse Management (Hort 3002W; University of Minnesota), students focus their learning of sustainability by writing...

Micro-manufacturing emerged in the last years as a new engineering area with the potential of increasing peoples’ quality of life through the production of innovative micro-devices to be used, for example, in the biomedical, micro-electronics or telecommunication sectors. The possibility to...

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...

Voluntary environmental programs (VEPs) have become increasingly popular around the world to address energy efficiency issues that mandatory building codes have not been able to tackle. Even though the utility of voluntary schemes is widely debated, they have become a <em>de facto</em> reality for many...

Human society is now at the beginning of a transition from fossil-fuel based primary energy sources to a mixture of renewable and nuclear based energy sources which have a lower Energy Return On Energy Invested (EROEI) than the older fossil based sources. This paper examines the evolution of...

Academic and policy interest in ecological footprint analysis has grown rapidly in recent years. To date, however, the application of ecological footprint analysis to tourism has been limited. This article aims to discuss the potential of ecological footprint analysis to assess sustainability in...