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Abstract: Two-thirds of input energy for electricity generation in the USA is lost as heat during conversion processes. Additionally, 12.5% of primary fuel and 20.3% of electricity are employed for space heating, water heating, and refrigeration where low-grade heat could suffice. The potential for harnessing waste heat from power generation and thermal processes to perform such tasks is assessed. By matching power plant outlet streams with applications at corresponding temperature ranges, sufficient waste heat is identified to satisfy all USA space and water heating needs. Sufficient high temperature exhaust from power plants is identified to satisfy 27% of residential air conditioning with thermally activated refrigeration, or all industrial refrigeration and process heating from 100 to 150 °C. Engine coolant and exhaust is sufficient to satisfy all air conditioning and 68% of electrical demands in vehicles. Overall, this study demonstrates the potential to reduce USA primary energy demand by 12% and CO2 emissions by 13% through waste heat recovery. A detailed analysis of thermal energy demand in pulp and paper manufacturing is conducted to demonstrate the methodology for improving the fidelity of this approach. These results can inform infrastructure and development to capture heat that would be lost today, substantially reducing USA energy intensity. [Copyright &y& Elsevier]

Wind-generated electricity is a growing renewable energy resource. Because wind results from the uneven heating (and resulting pressure gradients) of the Earth, future wind resources may be affected by anticipated climate change. Many studies have used global and regional climate models to predict trends in the future wind resource over the continental United States. While some of these studies identified regions that are expected to gain wind energy, their results often come with a high degree of uncertainty, and lack of agreement across different climate models. In this paper we focus on wind energy density as a measure of the available wind resource over the continental United States. We estimate the change in wind energy density from the period 1968–2000 to the period 2038–2070 by using output from four regional climate models from the North American Regional Climate Change Assessment Program (NARCCAP). We find strong agreement across all 4 models that the wind energy resource is expected to increase in parts of Kansas, Oklahoma, and northern Texas – a region already in possession of both large scale generating capacity and political support for wind energy. [ABSTRACT FROM AUTHOR]

Abstract: Since the turn of the 21st century, the onshore wind industry has seen significant growth due to the falling cost of wind generated electricity. This growth has coincided with an interest in the development of offshore wind farms. In Europe, governments and developers have begun establishing small to medium sized wind farms offshore to take advantage of stronger and more constant winds and the relative lack of landowner conflicts. In the U.S., several developers are in the planning and resource evaluation phases of offshore wind farm development, but no wind farms are currently operational or under construction. In this paper, we analyze the patterns of development in Europe and compare them to the U.S. We find significant differences in the patterns of development in Europe and the U.S. which may impact the viability of the industry in the U.S. We also discuss the policies used by European nations to stimulate offshore wind development and we discuss the potential impacts of similar policies in the U.S. [Copyright &y& Elsevier]

Abstract: High expansion of power demand is expected in the Upper Rio Grande region of far west Texas as a result of both electrical demand growth and decommissioning of installed capacity. On the supply side, a notable deployment of renewable power technologies can be projected owing to the recent legislation of a new energy policy in Texas, which attempts to reach 10,000 installed MWe of renewable capacity for 2025. Power generation fueled by natural gas might consistently expand due to the encouraged use of this fuel. In this context, the array of participating technologies can be optimized within a sustainability framework, which translates into a multi-objective optimization problem. In this paper, the problem is formulated and solved to determine supply shares for some chosen technologies based on both renewable power conversion and natural gas use. The exergetic and economic costs are established as primary competing factors. The deployment of renewable power technologies hypothetically follows the Gompertz growth model, which is constrained by exergetic self sustenance. The solution is given as a Pareto tradeoff front for arrays of optimal technologies and capacities. Additionally, the sustainability of these arrays is analyzed through indicators, and the current goal for renewable power technologies is discussed. [Copyright &y& Elsevier]