Assessment of Operational Performance for an Integrated ‘Power to Synthetic Natural Gas’ System

This article presents a power to SNG (synthetic natural gas) system that converts hydrogen into SNG via a methanation process. In our analysis, detailed models for all the elements of the system are built. We assume a direct connection between a wind farm and a hydrogen generator. For the purposes of our calculations, we also assume that the hydrogen generator is powered by the renewable source over a nine-hour period per day (between 21:00 and 06:00), and this corresponds to the off-peak period in energy demand. In addition, a hydrogen tank was introduced to maximize the operating time of the methanation reactor. The cooperation between the main components of the system were simulated using Matlab software. The primary aim of this paper is to assess the influence of various parameters on the operation of the proposed system, and to optimize its yearly operation via a consideration of the most important constraints. The analyses also examine different nominal power values of renewables from 8 to 12 MW and hydrogen generators from 3 to 6 MW. Implementing the proposed configuration, taking into account the direct connection of the hydrogen generator and the methanation reactor, showed that it had a positive effect on the dynamics and the operating times of the individual subsystems within the tested configuration.

A Day-Ahead Scheduling Model of Electricity-Gas Integrated System with Power-to-Gas

In recent years, with the increasing of gas-fired power plants and the development of power-to-gas (P2G) technology, and the interdependence between the power system and the natural gas system has gradually deepened. This paper proposes a day-ahead optimal scheduling model for an electricity-gas integrated system. Based on P2G, it can realize the two-way movement of energy between the power system and the natural gas system, promote the coordinated and optimized operation of the two energy systems, and improve energy utilization. The model proposed in this paper minimizes the total cost of both systems. Firstly, the power system sub-model and the natural gas system sub-model in the collaborative optimization model are studied separately, and the constraints between the two systems are considered. Then, the piecewise linearization method and DC power flow simplification method are adopted, the nonlinear problem is transformed into a mixed integer linear programming problem. Finally, the load forecast value of the day-ahead dispatch is loaded, and the 24-hour dispatch result is obtained through the simulation platform, and the P2G is used for joint dispatch.

Flexible Dispatch for Integrated Power and Gas Systems Considering Power-to-Gas and Demand Response

Aiming at the problem of insufficient flexibility of the power system caused by large-scale wind power grid integration, a flexible economic dispatch model of the electricity-gas integrated system that considers power-to-gas and demand responses is proposed. First, it elaborates on the scheduling flexibility and demand response model. Secondly, the power system and the natural gas system are regarded as different stakeholders; with the goal of minimizing their respective operating costs, a two-tier distributed coordination optimization model of electricity and gas system is established. In order to achieve the coordination and optimization of the upper and lower systems, slack variables are introduced to describe the infeasible part of the power system scheduling results in the natural gas system and are used for interactive iterative solution of the model. The numerical results of the revised IEEE 30-node power system and 10-node natural gas system illustrate the effectiveness and necessity of the proposed model, as well as the superiority of comprehensively considering power-to-gas and demand response in improving the flexibility and economy of the power system.

Optimal Planning of Electricity-Natural Gas Coupling System Considering Power to Gas Facilities

Bidirectional coupling systems for electricity and natural gas composed of gas units and power-to-gas (P2G) facilities improve the interactions between different energy systems. In this paper, a combined optimization planning method for an electricity-natural gas coupling system with P2G was studied. Firstly, the characteristics of the component model of the electricity-natural gas coupling system were analyzed. The optimization planning model for the electricity-natural gas coupling system was established with the goal of minimizing the sum of the annual investment costs and the annual operation costs. Based on the established model, the construction statuses for different types of units, power lines, and pipelines and the output distribution values for gas units and P2G stations were optimized. Then, the immune algorithm was proposed to solve the optimization planning model. Finally, an electricity-natural gas coupling system composed of a seven-node natural gas system and a nine-node power system was taken as an example to verify the rationality and effectiveness of the model under different scenarios.

Principales novedades para el sector del gas natural que resultan de las circulares de la Comisión Nacional de los Mercados y la Competencia.

LABURPENA: Gas naturalaren arloan daukagun sistema deskribatzen du lan honek, abiapuntu garbia jarrita: 1/2019 Errege Lege Dekretua bete beharrez MLBNk onartu zituen lehen zirkularrak. Zirkularrek instalazioetarako sarbidea, balantzea eta ordainsaria arautzen dituzte, baita aktibo horien kostua berreskuratzeko behar diren bidesariak ere. Sarbidearen zirkularrak «sistemaren birtualizazioa» amaitzen du, hau da, GNL-tanga bakarra sortzen du, hartara —espero izatekoa denez— efizientzia handiago lortzeko eta prezioak jaisteko. Balantze-zirkularraren ardatza iruzurra prebenitzea da; eska daitezkeen bermeak doitu, eta, urraketa larrietan, eragiketak desegitea ahalbidetzen du. Ordainsari-metodologiek ordainsariak murriztea ekarriko dute, arrisku txikiko jarduerak kosturik txikienean egin behar direla dioen printzipioa aintzat hartuta. Bidesarien bidez, ordainsari hori berreskuratu egingo da, hain zuzen ere 2021eko urtarrilaren 1ean hasten den sei urteko ordainsari-aldian. ABSTRACT: This work describes the natural gas system that results from the first regulations (circulars) approved by the CNMC according to the Royal Decree-Law 1/2019. The circulars regulate third party access to the facilities, their balance and remuneration, as well as the tariffs necessary to recover the cost of these assets. The access circular culminates the “virtualization of the system” with the creation of a single LNG tank that will hopefully allow for greater efficiency and lower prices. The balance circular is focused on preventing fraud. It readjusts the required guarantees and, in serious infringements, allows operations to be undone. The retribution methodologies will entail the reduction of the remuneration according to the principle of carrying out a low-risk activity at the lowest cost. Through the corresponding tariffs, this remuneration will be recovered during the six-year period that begins on January 1, 2021. RESUMEN: Este trabajo describe el sistema de gas natural que resulta de las primeras circulares aprobadas por la CNMC en cumplimiento del Real Decreto-ley 1/2019. Las circulares regulan el acceso a las instalaciones, su balance y retribución, así como los peajes necesarios para recuperar el coste de esos activos. La circular de acceso culmina la «virtualización del sistema» con la creación de un tanque único de GNL que permitirá, cabe esperar, mayor eficiencia y una reducción de precios. La circular de balance se centra en prevenir el fraude. Reajusta las garantías exigibles y, en incumplimientos graves, permite deshacer operaciones. Las metodologías de retribución supondrán la reducción de las retribuciones atendiendo al principio de realización de una actividad de bajo riesgo al menor coste. A través de los peajes se recuperará esa retribución durante el periodo retributivo de seis años que se inicia el 1 de enero de 2021.