Toward a sustainable global energy supply infrastructure : net energy balance and density considerations

This paper complements previous work on the economics of different energy resources by examining the growth potential of alternative electricity supply infrastructures as constrained by innate physical limits. Coal-fired generation meets the criteria of longevity (abundance of energy source) and scalability (effective capability to expand to the multi-terawatt level) which are critical for a sustainable energy supply chain, but it carries a very heavy carbon footprint. Renewables and nuclear power meet both the longevity and climate friendliness criteria. However, they vary in terms of their ability to deliver net energy at a scale needed for meeting a huge global energy demand. The low density of renewable resources for electricity generation and the current intermittency of many renewables limit their ability to achieve high rates of growth. And a significant global increase in nuclear power deployment could engender serious risks related to proliferation, safety, and waste disposal. Unlike renewable sources of energy, nuclear power is an unforgiving technology because human lapses and errors can have ecological and social impacts that are catastrophic and irreversible. The transition to a low carbon economy is likely to prove much more challenging than some optimists have claimed.Energy Production and Transportation,Climate Change Mitigation and Green House Gases,Energy and Environment,Environment and Energy Efficiency,Energy Demand

Towards a Sustainable Global Energy Supply Infrastructure: Net Energy Balance and Density Considerations

This paper employs a framework of dynamic energy analysis to model the growth potential of alternative electricity supply infrastructures as constrained by innate physical energy balance and dynamic response limits. Coal- red generation meets the criteria of longevity (abundance of energy source) and scalability (ability to expand to the multi-terawatt level) which are critical for a sustainable energy supply chain, but carries a very heavy carbon footprint. Renewables and nuclear power, on the other hand, meet both the longevity and environmental friendliness criteria. However, due to their substantially di¤erent energy densities and load factors, they vary in terms of their ability to deliver net excess energy and attain the scale needed for meeting the huge global energy demand. The low power density of renewable energy extraction and the intermittency of renewable ows limit their ability to achieve high rates of indigenous infrastructure growth. A signi cant global nuclear power deployment, on the other hand, could engender serious risks related to proliferation, safety, and waste disposal. Unlike renewable sources of energy, nuclear power is an unforgiving technology because human lapses and errors can have ecological and social impacts that are catastrophic and irreversible. Thus, the transition to a low carbon economy is likely to prove much more challenging than early optimists have claimed.dynamic energy analysis; alternative electricity supply; coal; nuclear energy

Maltreated children in the Looked After System: a comparison of outcomes for those who go home and those who do not

This project focuses on the consequences of decisions to reunify children who had entered the looked-after system for abuse or neglect. It compares the progress and outcomes of a sample of maltreated children who either went home or remained in the looked-after system

A content analysis of black female athletes and white female athletes in sports magazines

Literature suggests that female athletes receive less coverage in media than male athletes and that representation more often focuses on femininity than athleticism. Yet factors other than gender may influence media representation. Race and gender of target readers may impact representation of female athletes. This study reports the results of a content analysis of representations of white and black female athletes in 92 magazines. Representations of black female and white female athletes in Sports Illustrated, Sports Illustrated for Women and Her Sports from two different time periods, 2000-2002 and 2004-2008, were compared. Results reveal that the race of the female athlete and the gender of the reading audience affect the depiction of the athlete as primarily athletic or feminine