Linepack planning models for gas transmission network under uncertainty

Open market transient behaviours create challenges for National Grid, the UK gas transmission network operator, in meeting limits on pressure and linepack, i.e. the quantity of gas in the network. In this paper, four mixed-integer linear programming models are proposed for the optimal linepack planning to compensate for the fluctuation of gas demand. The first model minimises total deviation between planned and targeted linepacks such that all the customer’s demand and other network constraints are satisfied. The second model determines actions, including timings, to minimise total cost for resolving the gas deficit. We then extend this to a third model to deal with the periodical supply shortfall in the gas transmission network, and a fourth model to investigate the impact of compressor failure on the linepack management. The efficiency of these models is investigated and validated using real case study data. Experimental results show that our models can produce the optimal linepack plans under certain scenarios that current tools at National Grid cannot achieve

An Integrated Approach for Reliability Evaluation of Electric Power Systems Considering Natural Gas Network Reliability

With the rapid increase of demand for electric power and the growing complexity of the electric system, the reliable operation of electric systems is facing new challenges. Meanwhile, natural gas has been widely used in transportation, electricity generation, and heating. In addition, gas-fired turbines play a growing vital role in the generation of electricity. However, all the facilities in a natural gas network are subject to failures. The operation of gas-fired turbines will be affected by the status of natural gas network, and the insufficient supply of natural gas may cause the output of gas turbine units to reduce to zero. This power decrease may further influence the operation of power systems. Therefore, it is quite urgent to quantify the influence of natural gas networks on the power system reliability. A deep understanding of the operation of natural gas network is needed to quantify the impact that natural gas networks will bring to the power system reliability. The main facilities in a natural gas network are natural gas pipelines, compressor stations and natural gas sources. Additionally, the mathematical failure models have been developed for these facilities to build a reliability analysis framework for the gas network. The mass flow of natural gas at different failure conditions is analyzed by the maximum flow algorithm. Case studies are conducted on a modified Europe Belgium natural gas network to analyze the influences of different failures on the maximum flow of natural gas. The main problem discussed in this thesis is related to how the natural gas network operation status influences the reliability of power system. The coupling unit is the gas-fired turbine between and electric and gas infrastructures, while the simplified gas-fired turbine model used in this work shows a linear relation among the power generation and the mass flow of natural gas. In this thesis, reliability evaluation is performed based on the hierarchical level II which contains the generation system and the transmission system. The optimal power flow analysis has been conducted for the reliability evaluation. Based on the results of power flow, the status of load shedding can be obtained in a power system. Then, system reliability states can be determined. Failure statuses of both the natural gas network and electric system are simulated by Monte Carlo Simulation. Case studies are conducted on the RTS-79 system and the modified Europe Belgium natural gas network by using MATLAB and IBM CPLEX. The results indicate that the reliability of system decreases

Kualitas Produk dan Harga Mempengaruhi Konsumen Dalam Memasang Jaringan Gas Rumah Tangga Di Kelurahan Wonosari Kecamatan Prabumulih Utara Kota Prabumulih

The development of gas distribution networks for households is one of the national priority programs aimed at energy diversification, reducing subsidies, providing clean and cheap energy as well as a complementary program for the conversion of kerosene to Liquefied Petroleum Gas (LPG) to accelerate the reduction of petroleum use. Through this program, people are expected to get cleaner, safer, and cheaper fuel. With the realization of the household gas network in Prabumulih City, the community can use the household gas network. The success of the natural gas network program for households cannot be separated from the hard work of the City Government to socialize the household natural gas network. To solve the main problems faced by the company, a descriptive analysis method is used. Total customer population 2443 customers. Then the sample obtained using the formula is 340. Based on the results obtained, it can be seen that product quality and price have a positive and significant effect on the consumer's decision to install a gas network in Wonosari Village, Prabumulih Utara District, Prabumulih City, Prabumulih City, this can be seen from the value of F count which can be F counted 386,255> F table 3.04 with a significance value (sig) of 0,000, much smaller than 0.05, then the hypothesis H3 in this study is proven, accepted. Keywords: Product Quality, Price and Consumer Decision

A Dynamic Equivalent Energy Storage Model of Natural Gas Networks for Joint Optimal Dispatch of Electricity-Gas Systems

The development of energy conversion techniques enhances the coupling between the gas network and power system. However, challenges remain in the joint optimal dispatch of electricity-gas systems. The dynamic model of the gas network, described by partial differential equations, is complex and computationally demanding for power system operators. Furthermore, information privacy concerns and limited accessibility to detailed gas network models by power system operators necessitate quantifying the equivalent energy storage capacity of gas networks. This paper proposes a multi-port energy storage model with time-varying capacity to represent the dynamic gas state transformation and operational constraints in a compact and intuitive form. The model can be easily integrated into the optimal dispatch problem of the power system. Test cases demonstrate that the proposed model ensures feasible control strategies and significantly reduces the computational burden while maintaining high accuracy in the joint optimal dispatch of electricity-gas systems. In contrast, the existing static equivalent model fails to capture the full flexibility of the gas network and may yield infeasible results.Comment: 12 pages, 8 figure