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Miller, Mackay

Publications and source records attributed to Miller, Mackay.

High-Penetration Photovoltaic Planning Methodologies

The main objective of this report is to provide an overview of select U.S. utility methodologies for performing high-penetration photovoltaic (HPPV) system planning and impact studies. This report covers the Federal Energy Regulatory Commission's orders related to photovoltaic (PV) power system interconnection, particularly the interconnection processes for the Large Generation Interconnection Procedures and Small Generation Interconnection Procedures. In addition, it includes U.S. state interconnection standards and procedures. The procedures used by these regulatory bodies consider the impacts of HPPV power plants on the networks. Technical interconnection requirements for HPPV voltage regulation include aspects of power monitoring, grounding, synchronization, connection to the overall distribution system, back-feeds, disconnecting means, abnormal operating conditions, and power quality. This report provides a summary of mitigation strategies to minimize the impact of HPPV. Recommendations and revisions to the standards may take place as the penetration level of renewables on the grid increases and new technologies develop in future years.

14 SOLAR ENERGY↗

Software Comparison for Renewable Energy Deployment in a Distribution Network

The main objective of this report is to evaluate different software options for performing robust distributed generation (DG) power system modeling. The features and capabilities of four simulation tools, OpenDSS, GridLAB-D, CYMDIST, and PowerWorld Simulator, are compared to analyze their effectiveness in analyzing distribution networks with DG. OpenDSS and GridLAB-D, two open source software, have the capability to simulate networks with fluctuating data values. These packages allow the running of a simulation each time instant by iterating only the main script file. CYMDIST, a commercial software, allows for time-series simulation to study variations on network controls. PowerWorld Simulator, another commercial tool, has a batch mode simulation function through the 'Time Step Simulation' tool, which obtains solutions for a list of specified time points. PowerWorld Simulator is intended for analysis of transmission-level systems, while the other three are designed for distribution systems. CYMDIST and PowerWorld Simulator feature easy-to-use graphical user interfaces (GUIs). OpenDSS and GridLAB-D, on the other hand, are based on command-line programs, which increase the time necessary to become familiar with the software packages.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Comparative Analysis and Considerations for PV Interconnection Standards in the United States and China

The main objectives of this report are to evaluate China's photovoltaic (PV) interconnection standards and the U.S. counterparts and to propose recommendations for future revisions to these standards. This report references the 2013 report Comparative Study of Standards for Grid-Connected PV System in China, the U.S. and European Countries, which compares U.S., European, and China's PV grid interconnection standards; reviews various metrics for the characterization of distribution network with PV; and suggests modifications to China's PV interconnection standards and requirements. The recommendations are accompanied by assessments of four high-penetration PV grid interconnection cases in the United States to illustrate solutions implemented to resolve issues encountered at different sites. PV penetration in China and in the United States has significantly increased during the past several years, presenting comparable challenges depending on the conditions of the grid at the point of interconnection; solutions are generally unique to each interconnected PV installation or PV plant.

14 SOLAR ENERGY↗

Competitive Electricity Market Regulation in the United States: A Primer

The electricity system in the United States is a complex mechanism where different technologies, jurisdictions and regulatory designs interact. Today, two major models for electricity commercialization operate in the United States. One is the regulated monopoly model, in which vertically integrated electricity providers are regulated by state commissions. The other is the competitive model, in which power producers can openly access transmission infrastructure and participate in wholesale electricity markets. This paper describes the origins, evolution, and current status of the regulations that enable competitive markets in the United States.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Comparison of Standards and Technical Requirements of Grid-Connected Wind Power Plants in China and the United States

The rapid deployment of wind power has made grid integration and operational issues focal points in industry discussions and research. Compliance with grid connection standards for wind power plants (WPPs) is crucial to ensuring the reliable and stable operation of the electric power grid. This report compares the standards for grid-connected WPPs in China to those in the United States to facilitate further improvements in wind power standards and enhance the development of wind power equipment. Detailed analyses of power quality, low-voltage ride-through capability, active power control, reactive power control, voltage control, and wind power forecasting are provided to enhance the understanding of grid codes in the two largest markets of wind power. This study compares WPP interconnection standards and technical requirements in China to those in the United States.

17 WIND ENERGY↗

U.S. Laws and Regulations for Renewable Energy Grid Interconnections

Rapidly declining costs of wind and solar energy technologies, increasing concerns about the environmental and climate change impacts of fossil fuels, and sustained investment in renewable energy projects all point to a not-so-distant future in which renewable energy plays a pivotal role in the electric power system of the 21st century. In light of public pressures and market factors that hasten the transition towards a low-carbon system, power system planners and regulators are preparing to integrate higher levels of variable renewable generation into the grid. Updating the regulations that govern generator interconnections and operations is crucial to ensure system reliability while creating an enabling environment for renewable energy development. This report presents a chronological review of energy laws and regulations concerning grid interconnection procedures in the United States, highlighting the consequences of policies for renewable energy interconnections. Where appropriate, this report places interconnection policies and their impacts on renewable energy within the broader context of power market reform.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Grid-Integrated Distributed Solar: Addressing Challenges for Operations and Planning, Greening the Grid

Greening the Grid provides technical assistance to energy system planners, regulators, and grid operators to overcome challenges associated with integrating variable renewable energy into the grid. This document introduces a brief overview of common technical impacts of PV on distribution systems and operations, as well as emerging strategies for successfully addressing some of the priority issues.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Comparative Study of Standards for Grid-Connected Wind Power Plant in China and the U.S.

The rapid deployment of wind power has made grid integration and operational issues focal points in industry discussions and research. Compliance with grid connection standards for wind power plants (WPP) is crucial to ensuring the safe and stable operation of the electric power grid. The standards for grid-connected WPPs in China and the United States are compared in this paper to facilitate further improvements to the standards and enhance the development of wind power equipment. Detailed analyses in power quality, low-voltage ride-through capability, active power control, reactive power control, voltage control, and wind power forecasting are provided to enhance the understanding of grid codes in the two largest markets of wind power.

17 WIND ENERGY↗

Methods for Analyzing the Economic Value of Concentrating Solar Power with Thermal Energy Storage

Concentrating solar power with thermal energy storage (CSP-TES) provides multiple quantifiable benefits compared to CSP without storage or to solar photovoltaic (PV) technology, including higher energy value, ancillary services value, and capacity value. This report describes modeling approaches to quantifying these benefits that have emerged through state-level policymaking in the United States as well as the potential applicability of these methods in China. The technical potential for CSP-TES in China is significant, but deployment has not yet achieved the targets established by the Chinese government. According to the 12th Five Year Plan for Renewable Energy (2011-2015), CSP was expected to reach 1 GW by 2015 and 3 GW by 2020 in China, yet as of December 2014, deployment totaled only 13.8 MW. One barrier to more rapid deployment is the lack of an incentive specific to CSP, such as a feed-in tariff. The 13th Five Year Plan for Solar Generation (2016-2020), which is under development, presents an opportunity to establish a feed-in tariff specific to CSP. This report, produced under the auspices of the U.S.-China Renewable Energy Partnership, aims to support the development of Chinese incentives that advance CSP deployment goals.

47 OTHER INSTRUMENTATION↗

Status Report on Power System Transformation: A 21st Century Power Partnership Report

This report has three primary goals: (1) to articulate the concept of power system transformation; (2) to explore the current global landscape of ‘innovations’ that constitute power system transformation and provide evidence of how these innovations are emerging; and (3) to suggest an analytical framework for assessing the status of power system transformation on an on-going basis.

14 SOLAR ENERGY↗

Methods for Procuring Power System Flexibility, Greening the Grid

Greening the Grid provides technical assistance to energy system planners, regulators, and grid operators to overcome challenges associated with integrating variable renewable energy into the grid. This document, part of a Greening the Grid toolkit, introduces administrative and incentive-based mechanisms for procuring a cost-effective mix of flexibility sources.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Grid Integration and the Carrying Capacity of the U.S. Grid to Incorporate Variable Renewable Energy

In the United States and elsewhere, renewable energy (RE) generation supplies an increasingly large percentage of annual demand, including nine U.S. states where wind comprised over 10% of in-state generation in 2013. This white paper summarizes the challenges to integrating increasing amounts of variable RE, identifies emerging practices in power system planning and operation that can facilitate grid integration, and proposes a unifying concept—economic carrying capacity—that can provide a framework for evaluating actions to accommodate higher penetrations of RE. There is growing recognition that while technical challenges to variable RE integration are real, they can generally be addressed via a variety of solutions that vary in implementation cost. As a result, limits to RE penetration are primarily economic, driven by factors that include transmission and the flexibility of the power grid to balance supply and demand. This limit can be expressed as economic carrying capacity, or the point at which variable RE is no longer economically competitive or desirable to the system or society.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Power Systems of the Future: A 21st Century Power Partnership Thought Leadership Report

This report summarizes key forces driving transformation in the power sector around the world, presents a framework for evaluating decisions regarding extent and pace of change, and defines pathways for transformation. Powerful trends in technology, policy environments, financing, and business models are driving change in power sectors globally. In light of these trends, the question is no longer whether power systems will be transformed, but rather how these transformations will occur. Three approaches to policy and technology decision-making can guide these transformations: adaptive, reconstructive, and evolutionary. Within these approaches, we explore the five pathways that have emerged as viable models for power system transformation.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗