Adequacy Of Grid Research Articles

Stochastic Dominance of Renewables to Replace Hydropower Under Policy Uncertainty

Regional energy managers and decision-makers face a world where climate change is introducing uncertainty over future power generation, as well as financial impacts from potential carbon taxation. A unique opportunity to explore is the rising interest in hydropower substitution with renewable resources, either to promote ecosystem services such as increasing the survivability of migratory fish or mitigating future loss of generation due to severe drought conditions. To address these concerns, a case study of the Columbia River Basin was conducted to evaluate the substitution of four Lower Snake River dams. A multistage methodology was chosen to evaluate grid adequacy, climate change performance, and the implications of tax uncertainty on the substitution portfolios. A specialized energy model was used to provide the adequacy and input for a Monte Carlo simulation to test the impact of an uncertain tax. The outcome is a carbon tax strategy region that suggests preferences under different taxes for risk-averse decision makers, alongside adequacy and climate metrics. We conclude that policymakers should consider a carbon tax between <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\$ $ </tex-math></inline-formula> 86 and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\$ $ </tex-math></inline-formula> 132 to incentivize a portfolio that marginally reduces emissions compared to the pre-dam removal baseline or a tax greater than <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\$ $ </tex-math></inline-formula> 135 to incentivize another portfolio that significantly reduces emissions. This study makes three important contributions: (1) it provides a methodology for evaluating electricity generating portfolios in the presence of a carbon tax, (2) it evaluates adequacy metrics for technology substitutions with intermittent alternatives and climate change impacts, and (3) it offers specific guidance for energy policy making.

Can graph properties determine future grid adequacy for power injection diversity?

Engineers need new tools to design future power grids able to accommodate an increasing diversity of power injection operating states. Graph-based grid expansion tools are an emerging approach that exploits the underlying graph properties of power grids to inform preliminary stages of decision-making. The simplicity of graph-based approaches circumvents the need for computationally-intensive operations modeling, but extensive testing on its effectiveness in capturing and improving actual grid performance is lacking. This work provides experimental results that explore the efficacy of four graph-based grid-expansion approaches in improving grid adequacy. We rank and compare grid expansion options using four graph metrics and three inadequacy metrics to see whether graph metrics are good predictors of grid adequacy. Results for a 6- and a 118-bus test system show that grid designs that are top-ranking in terms of the graph metrics are not necessarily top-ranking in terms of the grid inadequacy metrics, and vice versa. Nonetheless, high-ranking grid designs in terms of some graph metrics can be high-ranking as well in terms of some grid inadequacy metrics – an observation that can be useful in some applications. The case studies illustrate that using the four graph-based grid expansion heuristics explored may not necessarily lead to optimal grid adequacy. How prevalent this observation is to other test systems and actual grids and whether there exist special classes of grids wherein graph-based grid expansion result in optimal grid adequacy will be interesting areas for future work.

Optimal integration assessment of solar PV in Japan’s electric power grid

Japan has faced the rapid penetration of solar PV, and specific power service areas actually experience technical difficulty in integrating massive PV into the power grids. By developing an optimal power grid model with 352 buses and 441 power transmission lines in an hourly temporal resolution through 8,760 h, this manuscript aims to analyze the optimal integration of solar PV into a bulk power transmission network in Japan and to identify the best location of PV to be installed in the grid so as to minimize total power system cost. For optimizing PV installation in Japan, computational results recommend the deployment of PV system in the area with sufficient grid capacity and higher solar radiation, because enough grid adequacy is necessary to efficiently control PV output and higher solar insolation leads to reduce required PV capacity and the associated investment cost. In order to realize optimal PV integration in Japan, policy recommendation is to institutionalize the scheme informing preferable locations of PV integration in a power grid, such as developing a PV installable map or implementing a zoning regulation of the grid connection.

Assessing the Impact of Cybersecurity Attacks on Power Systems

Cybersecurity is an emerging challenge for power systems, as it strongly affects their reliability and the whole energy system cost. The paper uses several Unit Commitments (UC) models, applying different methods to tackle renewables’ uncertainty. The selected power system is IEEE RTS 96. The UC models are used to assess the impact of different cybersecurity threats. The focus is to assess their impact on the total operating cost and the power grid adequacy to handle them. The comparison between the UC models shows that more robust UC models lead to higher total operating costs. The cost, unit dispatching, and energy mix evolution have a non-linear trend, depending on the power system characteristics and the cyberattacks types. However, the paper provides evidence of considerable price signals in the case of the examined cyberattacks. Each Transmission System Operator (TSO) should examine combinations of cyberattacks and operating conditions to identify crucial cases for system stability and power system cost operation. The applied methodology would also require substantial developments or supplementary approaches to assess cyberthreats at the distribution level.

Time-Accurate Coupling of Three-Degree-of-Freedom Parachute System with Navier–Stokes Equations

A parachute with payload is modeled as a three-degree-of-freedom system suitable for time-accurate coupling with the Navier–Stokes flow equations. The coupled equations of motion are formulated following an instantaneous Lagrangian–Eulerian approach, and solved using Newmark’s time-integration method. Flow solutions are computed by solving the Reynolds-averaged Navier–Stokes equations with structured overset grids. A sensitivity analysis is used to check the adequacy of grid and time-step requirements. The time-accurate coupling procedure is validated by comparing the results with a frequency-domain approach. The results are demonstrated for a real parachute system, including a comparison with the results based on the linear theory. Possible instabilities, such as divergence of inclination angle and flutter associated with fluctuating drag force, are predicted. The present work advances the fidelity of analysis procedures beyond those in current use based on loose coupling with the Navier–Stokes equations.

The Relationship among the Security, Efficiency and Adequacy of Electrical Power Grid Based on the Novel Evaluation Method

In order to study out the incidence relationship among security, efficiency and adequacy of Electrical Power Grid, a novel analyze model considering grid evolution and a relationship evaluation method is proposed in this paper. The model incorporates in fast dynamic and slow evolution. The former is based on an improved OPA model with low frequency load shedding control and the outage risk calculation. The latter is consists of increasing load, up-grading and constructing equipments including power plants, transformers and transmission lines, Using the model simulation the power grid development process. Based on the model, the customer outage risk caused by cascading failure is obtained in several times, the efficiency index and grid scale index are solved at the same times, these data are the basic data for analyze the incidence relationship among the security, efficiency and adequacy of electrical power grid. In this paper, the power grid of Kaifeng City in Henan Province, of China is used to simulate the evolution. The results show that the relationship among the security, efficiency and adequacy of grid is as exponential function, and a reasonable range of efficiency and adequacy of grid are proposed.

Evaluation of the Moroccan Power Grid Adequacy with Introduction of Concentrating Solar Power (CSP) Using Solar Tower and Parabolic Trough Mirrors Technology

The objective of this research work is to provide a effective assistance to all those who have to make decisions concerning the planning and implementation of projects in the renewable energy. Indeed, The integration in the Moroccan power grid of electrical power via Concentrating Solar Power (CSP) units using parabolic mirrors or solar tower is expected to have a significant impact on the reliability of the electrical system. In this context. Therefore, in this work, firstly, we assess the reliability of the Moroccan grid at hierarchical level HL1 (HL1: load covering under the assumption of infinite node) by use of a non-sequential Monte Carlo simulation in which CSP units (with parabolic through mirrors and with Solar tower) are introduced. Secondly objective of this paper is to assess the reliability of the Moroccan grid with an expected common integration of 14% wind and 14% solar energy.

Table of Contents

Abstract Features Skyrocketing Growth in Natural Gas Supply Seen George A. Lippman and John E. Uxer Jr. Grid Adequacy—Effect of Financial Freeze Short‐Term OK, but Infrastructure Renewal to Be Slowed Robert E. Willett Grid and Gas Adequacy—Generation Recent Generation Innovations Give Rise to New Planning Needs Samuel K. Scupham Grid Reliability Spare Transformers and More Frequent Replacement Increase Reliability, Decrease Cost Charles D. Feinstein and Peter A. Morris Columns Pipelines and Rates How Adequate Are Natural Gas Supplies This Year? Richard G. Smead Industry Advertising and Public Relations Harnessing Your Full Potential With Sustainability—An Environmental Communications Strategy Henry A. de La Garza