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[en] This study uses the total-factor energy productivity change index (TFEPCH) to investigate the changes in energy productivity of construction industry for 30 provincial regions in China from 2006 to 2015, adopting the improved Luenberger productivity index combined with the directional distance function. In addition to traditional economic output indicator, this study introduces building floor space under construction as a physical output indicator for energy productivity evaluation. The TFEPCH was decomposed into energy technical efficiency change and energy technical progress shift. Results indicate that, first, energy productivity of China’s construction industry decreased by 7.1% annually during 2006–2015. Energy technical regress, rather than energy technical efficiency, contributed most to the overall decline in energy productivity of China’s construction industry. Second, energy productivity in the central region of China decreased dramatically, by a cumulative sum of approximately 77.1%, since 2006, while energy productivity in the eastern and western regions decreased by over 54.3 and 65.3%, respectively. Only two of the 30 provinces considered—Hebei and Shandong—improved their energy productivity during 2006–2015. The findings presented here provide a basis for decision-making and references for administrative departments to set differentiated energy efficiency goals and develop relevant measures. Additionally, the findings are highly significant for energy and resource allocation of Chinese construction industry in different regions.
PurposeRenewable energies are promoted in order to reduce greenhouse gas emissions and the depletion of fossil fuels. However, plants for renewable electricity production incorporate specifically higher amounts of materials being rated as potentially scarce. Therefore, it is in question which (mineral) resources contribute to the overall resource consumption and which of the manifold impact assessment methods can be recommended to cover an accurate and complete investigation of resource use for renewable energy technologies.
MethodsLife cycle assessment is conducted for different renewable electricity production technologies (wind, photovoltaics, and biomass) under German conditions and compared to fossil electricity generation from a coal-fired power plant. Focus is given on mineral resource depletion for these technologies. As no consensus has been reached so far as to which impact assessment method is recommended, different established as well as recently developed impact assessment methods (CML, ReCiPe, Swiss Ecoscarcity, and economic scarcity potential (ESP)) are compared. The contribution of mineral resources to the overall resource depletion as well as potential scarcity are identified.
Results and discussionOverall resource depletion of electricity generation technologies tends to be dominated by fossil fuel depletion; therefore, most renewable technologies reduce the overall resource depletion compared to a coal-fired power plant. But, in comparison to fossil electricity generation from coal, mineral resource depletion is increased by wind and solar power. The investigated methods rate different materials as major contributors to mineral resource depletion, such as gallium used in photovoltaic plants (Swiss Ecoscarcity), gold and copper incorporated in electrical circuits and in cables (CML and ReCiPe), and nickel (Swiss Ecoscarcity and ReCiPe) and chromium (ESP) for stainless steel production. However, some methods lack characterization factors for potentially important materials.
ConclusionsIf mineral resource use is investigated for technologies using a wider spectrum of potentially scarce minerals, practitioners need to choose the impact assessment method carefully according to their scope and check if all important materials are covered. Further research is needed for an overall assessment of different resource compartments.
[en] Technology-intensive industries can be used as a major growth engine for resource poor country in the territories. For example, in the case of Korea, nuclear power and radiation technology industry was highly developed, and it was possible to obtain national interests such as solving energy problems within the country and exporting nuclear power plants. On the other hand, there are cases where national damage is caused by erroneous governmental policy-making on technology-intensive sectors. In this study, we analyzed cases of misguided governmental policy-making for technology-intensive industry and three factors were identified. And we tried to develop a rational policymaking model using three types of allison’s model in combination. The results of this study are expected to be useful for rational governmental policy-making processes for technology-intensive industries
[en] Highlights: • Analysis of the impact of reduced system inertia on primary frequency control. • Quantification of the primary frequency response requirements in the future GB low-inertia systems. • Assessment of the cost and emission driven by primary frequency control. • Evaluation of the benefits of EVs in supporting primary frequency control. • Identification of the synergy between primary frequency control support and “smart charging” strategy. - Abstract: System inertia reduction, driven by the integration of renewables, imposes significant challenges on the primary frequency control. Electrification of road transport not only reduces carbon emission by shifting from fossil fuel consumption to cleaner electricity consumption, but also potentially provide flexibility to facilitate the integration of renewables, such as supporting primary frequency control. In this context, this paper develops a techno-economic evaluation framework to quantify the challenges on primary frequency control and assess the benefits of EVs in providing primary frequency response. A simplified GB power system dynamic model is used to analyze the impact of declining system inertia on the primary frequency control and the technical potential of primary frequency response provision from EVs. Furthermore, an advanced stochastic system scheduling tool with explicitly modeling of inertia reduction effect is applied to assess the cost and emission driven by primary frequency control as well as the benefits of EVs in providing primary frequency response under two representative GB 2030 system scenarios. This paper also identifies the synergy between PFR provision from EVs and “smart charging” strategy as well as the impact of synthetic inertia from wind turbines.
[en] Highlights: • A multi-objective MPC strategy for residential heating with heat pumps is presented. • The simulations employ detailed models for heat pump and thermal energy storage. • The feedback of individual controllers on the electricity generation is included. • Results show a significant reduction in required generation capacity is possible. • Costs carried by the consumer rise when demand response is applied. - Abstract: Shifting residential space heating from the use of gas boilers towards the use of heat pumps is recognized as a method to reduce green house gas emissions and increase energy efficiency and the share of renewable energy sources. Demand response of these systems could aid in reducing peak loads on the electricity grid. Extra flexibility can be added in the form of a thermal energy storage tank. This paper proposes a multi-objective model predictive control strategy for such a system, which takes into account the users energy cost, the environmental impact of energy use and the impact of expanding the electricity generation capacity. This control strategy is used in a case study inspired by the Belgian electricity generation park with 500,000 heat pumps to investigate the effect of the size of a space heating storage tank on consumer cost, energy use and required electricity generation capacity. Results indicate that the proposed demand response strategy reduces the required peak load capacity substantially with only a small increase in costs for the consumer. When adding a large hot water storage tank, the required additional capacity is nearly eliminated. Independently of the required capacity, the controller shifts energy use from peak to base generating plants. Increasing the storage tank size increases the amount of energy that is shifted. However, when demand response is applied by using a space heating storage tank, the costs for the consumer always increase relative to the case without demand response or storage tank. If demand response is desired by the grid operator, heat pump owners should be encouraged to participate by remunerating them for their additional expenses.
[en] We investigate this study to examine the relationship between economic growth, freight transport, and energy consumption for 63 developing countries over the period of 1990–2016. In order to make the panel data analysis more homogeneous, we apply the income level of countries to divide the global panel into three sub-panels, namely, lower-middle income countries (LMIC), upper-middle income countries (UMIC), and high-income countries (HIC). Using the generalized method of moments (GMM), the results prove evidence of bidirectional causal relationship between economic growth and freight transport for all selected panels and between economic growth and energy consumption for the high- and upper-middle income panels. For the lower-middle income panel, the causality is unidirectional running from energy consumption to economic growth. Also, the results indicate that the relationship between freight transport and energy use is bidirectional for the high-income countries and unidirectional from freight transport to energy consumption for the upper-middle and lower-middle income countries. Empirical evidence demonstrates the importance of energy for economic activity and rejects the neo-classical assumption that energy is neutral for growth. An important policy recommendation is that there is need of advancements in vehicle technology which can reduce energy intensity from transport sector and improve the energy efficiency in transport activity which in turn allows a greater positive role of transport in global economic activity.
[en] The German Atomforum (DAtF) and the Kerntechnische Gesellschaft (KTG) held the annular meeting Nuclear Technology from 4th until 6th May 1982 in Mannheim. The structure,which was determined after various changes in the previous year, was retained year and should definitively decisive for further meetings: Three plenary sessions on Tuesday morning and Thursday morning and afternoon, three parallel technical sessions on Wednesday morning, and technical sessions in nine sessions (sections) on Tuesday and Wednesday afternoon. With a cutback to three days, maximum concentration has been achieved for such a wide-ranging meeting. However, an attractive lecture topic and the announcement of the participation of the Federal Minister of the Interior in the final session of the former participants observer on Friday could not prevent the loss of attendance.
[en] As 2018 draws to a close, there have been several developments that will mean the new year dawning with fresh uncertainties on the horizon for the global nuclear energy industry: Brexit and announcement of the Trump administration for a new policy framework for curtailing civil nuclear commerce with China are two of them.
[en] Highlights: • A dynamic model of Steam Turbine control valve and actuation systems is proposed. • An innovative study of the equations that rule the assembly movement is provided. • Control valve response and accuracy is analyzed in detail with test and simulation. • System upgrade is achieved with Electro-Hydrostatic Actuation technology. - Abstract: The paper describes a study conducted on the control valve and the actuation systems of a Steam Turbine. These devices are of utmost importance, as they rule the machine final power production and rotational speed, thus their accurate modelling is fundamental for a valuable dynamic analysis of the whole system. In particular, a dynamic model developed in the Matlab/Simulink environment is proposed, which supports the analysis of the operational stability of the hydro-mechanical system as well as the failure modes that it may face during operation. The model has been successfully validated through specific field tests conducted on the actuation system at a cogeneration plant located in the General Electric Oil & Gas - Nuovo Pignone facility of Florence. The proposed work also highlights the requirements that new actuation technologies should fulfill in order to meet control valve system performance criteria and is thus useful as both a methodological approach and a “virtual benchmark” allowing to validate in advance any new actuation system.
[en] Highlights: • Optimization model for BtL production considering competing utilization paths. • Supply chain with decentralized pre-treatment via torrefaction and fast pyrolysis. • Local supply curves are used to model diseconomies of scale in biomass supply. • Synthetic gasoline can be produced at a cost of 0.8–0.9 € per liter. • BtL feedstock costs are 20–50% higher compared with established consumers. - Abstract: Second generation biofuels offer the opportunity to mitigate emissions from the growing transportation sector while respecting the scarcity of arable land in agriculture. Biomass-to-liquid (BtL) concepts based on large-scale gasification are capable of using low-quality residual feedstock, such as wheat straw or forest residues, for the production of transportation fuels. However, large amounts of biomass feedstock are required to achieve the economic capacity of a synthesis plant. Depending on the steepness of the terrain and the role of feedstock owners, biomass potentials can only be utilized to a large extent at increasing costs per ton. Such diseconomies of scale are particularly problematic in the presence of already established value chains consuming the easily accessible and low-cost feedstock. As a result, second-generation biofuel supply chains face steep supply curves with sharply increasing unit costs. This article investigates the impact of established utilization paths on a large-scale biofuel production value chain. To do so, a mixed-integer linear model is presented which first determines the allocation of biomass resources to CHP plants and domestic consumers. Based on the resulting costs and supply curves, the model then determines the optimum configuration of the synfuel supply chain including locations and capacities of conversion plants, feedstock procurement and transportation. The model is applied to a case study covering six regions in south-central Chile. The total supply chain cost for the production of synthetic gasoline is estimated to amount to 0.8–0.9 € per liter. Feedstock costs of the synfuel supply chain are 20–50% higher in comparison to the price paid by CHP plants and households. The results indicate that both torrefaction and fast pyrolysis can be applied beneficially to utilize remote biomass resources which are less in demand by established consumers.