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The integration of multiple energy systems (MES) provides opportunities to explore the flexibility to accommodate more renewable energy. The concept and methodology of energy hub (EH) enable the standardized modeling of district MES. However, current EH formulations introduce nonlinearities into the modeling and present challenges to analysis and optimization. This paper proposes an automatic and linearized modeling method to formulate energy conversion in EHs, which simplifies the optimization of EH operations. On this basis, the flexibility of an EH is analyzed and quantitatively evaluated based on the ranks of the coupling matrices of the EH and its feasible operational region. Finally, an application of the linearized model on the interval optimization model is illustrated to show how it can suppress uncertainties and fluctuations in distributed renewable energy. A case study is used to demonstrate the effectiveness of the proposed model and the rationality of the flexibility analysis by comparing two EHs with different flexibilities. [ABSTRACT FROM AUTHOR]

Abstract: Demand response has proven to be a useful mechanism that produces important benefits for both the customer and the power system. In the context of an increasingly competitive electricity market, where prices are constantly rising and the presence of renewable energy resources is gaining prominence, this paper analyzes the flexibility potential of customers in the meat industry, based on the management of the most energy consuming process in this type of segment: cooling production and distribution. The effectiveness of the proposed actions has been successfully tested and validated in an active factory that produces cured ham in Spain, where savings of about 5% in the total annual cost of electricity have been assessed, together with power reductions in the range of 50% of the total peak demand of the studied facilities. Such results demonstrate the efficacy of these techniques, and they open the door to an innovative perspective on the evaluation of flexibility among customers which are traditionally considered rigid, providing a novel approach to the management of customer infrastructures in order to exploit their flexibility in electricity markets. [Copyright &y& Elsevier]

Abstract: Numerical simulations are essential to the understanding of the long-term geological storage of CO2. Physical modelling of geological storage of CO2 has been based on Darcy’s law, together with the equations of conservation of mass and energy. Modelling and simulations can be used to predict where CO2 is likely to flow, to interpret the volume and spatial distribution of CO2 under storage conditions, and to optimise injection operations. The state of the art of physical modelling and numerical simulation of CO2 dispersion is briefly reviewed in this paper, which calls for more accurate and more efficient modelling approaches. A systematic evaluation of the numerical methods used and a comparison between the streamline based methods and the grid based methods would be valuable. Multi-scale modelling may prove to be of great value in predicting the long-term geological storage of CO2, while highly accurate numerical methods such as high-order schemes may be employed in numerical simulations of CO2 dispersion for local transport calculations. [Copyright &y& Elsevier]

Abstract: The purpose of this paper is to identify the relations between transportation energy consumption and its impacted factors. We first analyze the current status of transportation energy consumption in China. Then, the logarithmic mean Divisia index (LMDI) technique is used to find the nature of the factors those influence the changes in transportation energy consumption. We find that: (1) In 2006, the transportation energy consumption increased by 7.63 times against that in 1980. (2) Up to 2006, the oil consumed by transportation accounted for 49.6% of that in the whole country, which almost equaled to the net oil import. (3) In the light of the increasing energy consumption intensity, the energy-utilization effectiveness of transportation sector has been declining gradually. (4) The transportation activity effect is the most important contributor to increase energy consumption in the transportation sector and the energy intensity effect plays the dominant role in decreasing energy consumption. [Copyright &y& Elsevier]

Abstract: Along with high-speed economic development and increasing energy consumption, the Chinese Government faces a growing pressure to maintain the balance between energy supply and demand. In 2009, China has become both the largest energy consumer and CO2 emitting country in the world. In this case, the inappropriate energy consumption structure should be changed. As an alternative, a suitable infrastructure for the implementation of renewable energy may serve as a long-term sustainable solution. The perspective of a 100% renewable energy system has been analyzed and discussed in some countries previously. In this process, assessment of domestic renewable energy sources is the first step. Then appropriate methodologies are needed to perform energy system analyses involving the integration of more sustainable strategies. Denmark may serve as an example of how sustainable strategies can be implemented. The Danish system has demonstrated the possibility of converting into a 100% renewable energy system. This paper discusses the perspective of renewable energy in China firstly, and then analyses whether it is suitable to adopt similar methodologies applied in other countries as China approaches a renewable energy system. The conclusion is that China’s domestic renewable energy sources are abundant and show the possibility to cover future energy demand; the methodologies used to analyse a 100% renewable energy system are applicable in China. Therefore, proposing an analysis of a 100% renewable energy system in China is not unreasonable. [ABSTRACT FROM AUTHOR]