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[en] Water consumption is emerging as an important issue potentially influencing the composition of future urban transportation networks, especially as projected urban populations are expected to outpace water availability and as alternative fuels and vehicles are being implemented in such regions. National and State policies aimed at reducing dependence on imported fuels and energy can increase local production of fuels and energy, impacting demand on local water resources. This article details the development of a model-based assessment on water consumption and withdrawal pertaining to the use-phase of conventional and alternative transportation modes based on regional energy and fuel production. An extensive literature review details water consumption from fuel extraction, processing, and distribution as well as power plant operations. Using Model-Based Systems Engineering principles and the Systems Modeling Language, a multi-level, multi-modal framework was developed and applied to the Metro Atlanta transportation system consisting of conventional and alternative vehicles across varying conditions. According to the analysis, vehicles powered by locally produced biofuels and electricity (assuming average local grid mix for charging) consume more water than locally refined gasoline and CNG-powered vehicles. Improvements in power plant technologies, electricity generation (e.g., use of solar and wind versus hydro power) and vehicle efficiencies can reduce such water consumption significantly. Total water withdrawal for each vehicle and fuel is significantly greater than water consumption. - Highlights: ► A model was made to assess the local water consumption due to conventional and alternatively powered vehicles in a city. ► Water consumed in the local and external production of various fuels was reviewed and included. ► Basic battery electric and biofuel powered vehicles consume on average more water than conventional gasoline and Compressed Natural Gas (CNG) vehicles in their use-phase. ► Policies promoting (local) energy independence can have adverse effects on local water consumption. ► Improvements in technology, power generation (use of wind and solar) reduces water consumption of electric vehicles.
[en] In accordance with the energy planning in China, within the “Twelfth Five-Year” period (2011–2015), the proportion of natural gas among primary energy consumption is expected to increase from the current 4% to 8%. In 2015, about 17 natural gas pipelines will be completed. This paper reviews the current situation of gas power generation, analyzes the main opportunities and obstacles of gas power generation development in China, and conducts a techno-economic assessment of the natural gas power generation, taking into account the role and the interaction of the multiple stakeholders in the natural gas industry chain. Taking a power plant fueled with the natural gas transported by the second West-to-East Pipeline as an example, it is found that the on-grid power price fluctuates upward with the rise of gas price and downward with the increase of annual utilization hours, and the influences of tax policies on the on-grid power price prove to be highly significant. As the analysis and calculation indicate, the environmental benefits of natural gas power generation ought to be strongly emphasized, compared with coal-fired power generation. Finally, this paper puts forward specific policy recommendations, from the perspectives of electricity price, gas price, tax, power grid dispatching, etc. - Highlights: ► Presents the opportunities and obstacles of gas power generation development in China. ► Analyzes the interactions of multiple stakeholders in the natural gas industry chain. ► Conducts a techno-economic assessment on the natural gas power generation. ► Discusses the responsibilities and risks of multiple stakeholders. ► Puts forward policy recommendations, from electricity price, gas price, tax, etc.
[en] Due to the increase in electricity generation capacity in the Netherlands and a new connection policy, transmission system operator (TSO) TenneT expects a significant increase in congestion in the Dutch transmission grid. To manage this, the Dutch government implemented redispatching, a method which is argued in the literature to potentially impose large congestion costs upon the TSO. A quantitative model of the Dutch electricity system was developed in order to evaluate this method. The outcomes were compared to the performance of three alternative congestion management methods. Regardless of the method, congestion costs were found to be substantially lower than in previous studies. Because combined-cycle gas turbines are the marginal generation technology in almost all cases, the costs of up and down regulation do not differ much. Consequently, the redispatching costs for the TSO are expected to be relatively low, and the opportunities for abuse of market power appear to be limited. While all the evaluated methods are effective and economically efficient, they have significantly different welfare effects. Market splitting creates significantly larger welfare effects than the different varieties of redispatching. - Highlights: ► Congestion management was recently introduced in the Netherlands. ► We quantitatively evaluate the effects of its application. ► We compare this to other congestion management methods. ► Given the specific situation that the marginal cost curve of production is flat, congestion costs are expected to be low.
[en] The Chilean electrical sector was deregulated in 1982, where unbundling was applied, and generation competition and marginal costing were introduced. Description of the main features of the generation market and system operation is presented, followed by a synthesis of the main achievements and difficulties experienced in the practical application. The experience with the troubles faced in the reformed power sector after 18 years is used to look at the possible advantages of the second stage of deregulation. The challenges of a new legislation, where the system is expected to join the second generation of deregulation are discussed. Advantage and risks of opening the energy market with a bidding system separate from ancillary service market are analysed. The experience with the troubles faced in the reformed power sector after 18 years is used to look at the possible advantages of the second stage of deregulation. (author)
[en] Local citizen-led initiatives relating to energy are developing strongly in Anglo-Saxon countries and a growing body of research is examining their innovative potential. In France, similar grassroots initiatives – albeit with certain specificities – only began to emerge recently and so far, very few studies have dealt with them. The purpose of this article is to propose an exploratory and in-depth analysis of one advanced French case: Le Mene', a pioneer in local energy autonomy. We examine the conditions under which the initiative emerged and the processes through which a grassroots innovation is formed. In studying this case (interviews, analysis of documents), comparing it with other sources of data (expert interviews, comparative observation of other initiatives) and taking stock of various social sciences studies, we show that a social innovation was produced in Le Mene' through the hybridisation of actors, sociotechniques and discourses. This initiative was innovative not only in terms of the scope of the mechanisms implemented, but also in terms of the social organisation behind the development of the projects and the capacity to use energy production as a social resource. Finally, we reflect on the possible diffusion of these grassroots initiatives and their policy implications in France. - Highlights: • The case study is the Le Mené, a pioneer case for local energy autonomy. • This case is an emerging grassroots innovation in France. • Hybridisation (combining diversity and frames) is at the centre of the innovation. • This study focuses on the hybridisation of actors, sociotechniques and discourses. • Examines the potential diffusion of grassroots initiatives in France
[en] This paper presents two methods for calculating long-run marginal electricity generation costs based on the techniques used for long-term expansion planning. According to the first method, long-run marginal costs are calculated as incremental costs required to supply additional demands-peak, shoulder and off-peak demands, to each hourly demand group separately. These costs include the present value of capital, fuel and operation and maintenance (O and M) costs throughout the planning period. In the second method, the long-run marginal capacity cost element is calculated as an additional/reduced cost resulting from bringing forward/postponing generation capacity investments, in order to supply incremented/decremented demands in every hour throughout the planning period. The annualized marginal capacity cost is allocated among the hours according to the distribution of the unsupplied energy, and is added to the energy marginal cost to obtain the long-run marginal cost. Both methods are implemented through models used for long-term optimal generation system expansion planning. In addition, the second method uses a chronological simulation of generation system operation. A detailed case study of the Israeli electric generation system is also presented. (author)
[en] Deregulation of electricity industry in Europe has tended to start with a grace period of energy surplus inherited from the previously expansive coordinated economies and further amplified by better resource utilisation from extended international trade. The regulatory challenge has therefore primarily been to allocate existing generation to consumers in an efficient way. However, as energy demand increases, due to economic growth, the challenge of providing new capacity surfaces. The Nordic region, which has been a pioneer in internationalising and deregulating electricity, is now approaching this stage, ahead of most of the rest of Europe. While the Nordic case is characterised by specificities related to hydropower it also raises the more general challenge of capacity expansion under a deregulated market economy. The article therefore discusses how the Nordic investment challenges of today shed light on more generic challenges that may become more general European challenges of tomorrow. In a final section, the article discusses policy options available to address the investment/price-hike challenge. The argument is put forward that recursion to some degree of coordinated governance might seem necessary if solutions are confined within large-scale technical systems. However, within the context of a small-scale decentralised technological development, one may be more confident of competitive solutions. (Author)
[en] We propose mathematical programming models for solving problems arising from planning and running an energy production process based on burning biomasses. The models take into account different aspects of the problem: determination of the biomasses to produce and/or buy, transportation decisions to convey the materials to the respective plants, and plant site locations. Whereas the 'running model' is linear, we propose two 'planning models', both of which are mixed-integer nonlinear programming problems. We show that a spatial branch-and-bound type algorithm applied to them is guaranteed to converge to an exact optimum in a finite number of steps
[en] Average market prices for intermittent generation technologies are lower than for conventional generation. This has a technical reason but can be exaggerated in the presence of market power. When there is much wind smaller amounts of conventional generation technologies are required, and prices are lower, while at times of little wind prices are higher. This effect reflects the value of different generation technologies to the system. But under conditions of market power, conventional generators with market power can further depress the prices if they have to buy back energy at times of large wind output and can increase prices if they have to sell additional power at times of little wind output. This greatly exaggerates the effect. Forward contracting does not reduce the effect. An important consequence is that allowing market power profit margins as a support mechanism for generation capacity investment is not a technologically neutral policy.
[en] Since the very beginning of the power systems reform process, one of the key questions posed has been whether the market, of its own accord, is able to provide satisfactory security of supply at the power generation level or if some additional regulatory mechanism needs to be introduced, and in the latter case, which is the most suitable approach to tackle the problem. This matter is undoubtedly gaining importance and it has taken a key role in the energy regulators' agendas. In this paper, we critically review and categorize the different approaches regulators can opt for to deal with the problem of guaranteeing (or at least enhancing) security of supply in a market-oriented environment. We analyze the most relevant regulatory design elements throughout an updated assessment of the broad range of international experiences, highlighting the lessons we have learned so far in a variety of contexts. Based on the analysis, we conclude by providing a set of principles and criteria that should be considered by the regulator when designing a security of supply mechanism. (author)