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Electricity is an important output of the global energy system. Large amounts of water can be consumed in the process of producing electricity. This article focuses on how that water is virtually transferred from power-generating regions to electricity-consuming areas. We propose two metrics, i.e., water substitution ratio and virtual water transfer loss, to assess the efficiency of water use for power generation and virtual transmission of water through the power transmission system, respectively. These metrics are used to estimate the effects of the West–East Electricity Transmission project in China on the water resources used in power-generating regions. Results show that the electricity delivered by the project increased from 228 TWh in 2008 to 683 TWh in 2017. With the construction of wind and solar energy projects, the growth rate of virtual water was slightly slower than that of the electricity transmitted. In 2017, 2.4 km3 of virtual water was transmitted eastward. The corresponding virtual water transfer loss throughout the transmission system was approximately 100 million m3. We estimate that the virtual water footprint of the project will exceed 4.4 km3 by 2030, which may affect the sustainability of water resources and the ecological environment in western regions of China.

Energy consuming appliances accounted for over 40% of the energy use and $17 billion in sales in the U.S. in 2014. Whether such amounts of money and energy were optimally combined to produce household energy services is not straightforwardly determined. The efficient allocation of capital and energy to provide an energy service has been previously approached, and solved with Data Envelopment Analysis (DEA) under constant returns to scale. That approach, however, lacks the scale dimension of the problem and may restrict the economic efficient models of an appliance available in the market when constant returns to scale does not hold. We expand on that approach to estimate returns to scale for energy using appliances. We further calculate DEA scale efficiency scores for the technically efficient models that comprise the economic efficient frontier of the energy service delivered, under different assumptions of returns to scale. We then apply this approach to evaluate dishwashers available in the market in the U.S. Our results show that (a) for the case of dishwashers scale matters, and (b) the dishwashing energy service is delivered under non-decreasing returns to scale. The results further demonstrate that this method contributes to increase consumers’ choice of appliances.

Fourteen students in a multiage middle school inclusive classroom engaged in literature circles while reading various short stories and novels during the course of one school semester. Students with special needs (n=7) believed literature circles helped them read, analyze, and discuss literature selections. They also showed gains in self-management skills. (Contains references.) (CR)

This article provides guidelines for designing effective instructional games for all students, including students with disabilities or other special learning needs. The benefits of instructional games, including student motivation and the ability of games to facilitate individualized instruction, are discussed. Sample instructional games, including Speech BINGO, Emotional Card Game, and Tic-Tac-Toe Math, are described. (CR)