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The 21st Century Power Partnership publications and webinars provide information about and analysis of market design and regulatory issues for clean energy and 21st century power systems. Published work appears in scientific journals and the National Renewable Energy Laboratory publications database.

Journal Articles, Technical Reports, and Brochures

Next-Generation Performance-Based Regulation: Emphasizing Utility Performance to Unleash Power Sector Innovation. September 2017.
Performance-based regulation (PBR) has established a pathway for reforming hundred-year-old regulatory structures to unleash innovations within 21st century power systems. The old regulatory paradigm, built to ensure safe and reliable electricity at reasonable prices from capital-intensive electricity monopolies, is adjusting to disruptive technological advances that are transforming the way electricity is generated, delivered, and consumed. PBR enables regulators to recognize the value electric utilities bring to customers by enabling advanced energy technologies and integrating smart solutions into the utility grid and utility operations. These changes in the electric energy system and customer capacities have catalyzed increased interest in motivating regulated entities to move beyond traditional cost-of-service performance regulation. This report addresses best practices and lessons gleaned from more than two decades of PBR in practice, and analyzes how those can be applied to design innovative PBR programs.    

Greening the Grid: Pathways To Integrate 175 Gigawatts of Renewable Energy into India's Electric Grid. June 2017.
The use of renewable energy (RE) sources, primarily wind and solar generation, is poised to grow significantly within the Indian power system. The Government of India has established an installed capacity target of 175 gigawatts (GW) of RE by 2022 that includes 60 GW of wind and 100 GW of solar, up from current capacities of 29 GW wind and 9 GW solar. Using advanced weather and power system modeling designed specifically for this project, the multi-institutional study team explored operational impacts of meeting India’s RE targets and identified actions that are favorable for integration. The study team’s primary tool was a detailed production cost model, which simulates optimal scheduling and dispatch of available power generation in a future year (2022) by minimizing total production costs subject to physical, operational, and market constraints. Read the overview to learn more.

Status of Power System Transformation 2017. June 2017.
Power sectors around the world are undergoing significant change due to the rapid uptake of new supply- and demand-side technologies. Large-scale wind and solar power as well as distributed energy resources are influencing the planning, operation, and profitability of power systems. Policymakers, utilities, and other stakeholders need to apply innovative approaches to transform the power system, with the objective to achieve sustainable, affordable and reliable electricity. This report provides an overview of current trends across the globe, with a focus on the integration of renewables and local grid development. A framework for assessing the status of power system transformation is also introduced and applied to Indonesia, South Africa, Mexico, and Australia.

Policies for Enabling Corporate Sourcing of Renewable Energy Internationally. May 2017.
Overview brochure
Interest in renewable energy (RE) procurement in new markets is on the rise. Corporations are increasing their commitments to procuring RE, motivated by an interest in using clean energy sources and reducing their energy expenses. Many large companies have facilities and supply chains in multiple countries, and are interested in procuring renewable energy in the grids where they use energy. The policy environment around the world plays a key role in shaping where and how corporations will invest in renewables. This report explores the policy and regulatory enabling environment for corporate sourcing of renewables.

Evolving Distributed Generation Support Mechanisms: Case Studies from United States, Germany, United Kingdom, and AustraliaMarch 2017.
Past distributed generation policies and market developments in the United States provide lessons learned. Additional case studies illustrate how several countries are pivoting away from historical forms of support for distributed PV toward more market-based schemes.

Transmission Challenges and Best Practices for Cost-Effective Renewable Energy Delivery across State and Provincial BoundariesMarch 2017.
Over the past ten years, China has seen tremendous growth in renewable energy development, accompanied by high levels of curtailment. This report details U.S. experiences in transmission scheduling, pricing, access, and allocation to illustrate implications for consideration in China.

Mexico's Regulatory Engagement in Bulk Electric Power System Planning: An Overview of U.S. Practices and ToolsJune 2016.
Mexico's transition to a modern wholesale power market will place new demands on how regulators evaluate and approve transmission expansion projects. Transmission projects in a modern wholesale market fulfill one of several needs, and utilities, regional transmission organizations (RTOs), and regulatory authorities in the United States have encountered comparable challenges in their market transitions to ensure projects meeting each type of need can be built. The purpose of this report is to open a window to view that experience. The report examines key practices of different U.S. jurisdictions that have moved from transmission planning to transmission approval, and it focuses on the role of the regulator in supporting a planning process that equitably meets identified needs.

Clean Restructuring: Design Elements for Low Carbon Wholesale Markets and Beyond. May 2016.
Overview brochure
Countries around the world are in various stages of reforming and restructuring their power systems to better meet development needs. Changes in technology, business models, societal needs, and environmental goals are increasing pressure for countries to consider improvements to their power systems. This report addresses key issues associated clean restructuring—the transition from traditional, vertically integrated utilities to competitive wholesale markets that rely on variable renewable electricity sources, demand response, and other clean energy options.

Status Report on Power System Transformation. May 2015.
Power system transformation is a complex, active process that is taking place at different rates and in different forms around the world. This transformation has multiple drivers, including technological advances, policy goals, and social change, and multiple enablers, especially policy, financial, and business model innovation. This report aims to bring the power system transformation picture into sharper focus, bolstering the evidence base for power system transformation by providing a collection of empirical examples of the types of innovations that are emerging around the world.

Report on India's Renewable Electricity Roadmap 2030: Toward Accelerated Renewable Electricity Deployment: Executive Summary. February 2015.
Published with participation from 21CPP by the National Institution for Transforming India (NITI Aayog) with support of the Confederation of Indian Industry, Shakti Sustainable Energy Foundation, and the Regulatory Assistance Project, this report outlines key recommendations and a framework for integrated policy strategy for rapid renewable electricity implementation that complements both existing and planned conventional power projects. The full report is available from the Confederation of Indian Industry.

Power Systems of the Future: A 21st Century Power Partnership Thought Leadership Report.
Also available as a two-page overview.
February 2015.
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, the report explores the five pathways that have emerged as viable models for power system transformation.

Making Coal Flexible: Getting From Baseload to Peaking Plant.
Also available in Mandarin. January 2015.
Power systems in the 21st century—with higher penetration of low-carbon energy, smart grids, and other emerging technologies—will favor resources that have low marginal costs and provide system flexibility. Such flexibility includes the ability to cycle on and off as well as run at low minimum loads to complement variations in output from high penetration of renewable energy. Can coal-fired power plants continue to operate cost-effectively if they cycle routinely? Yes, according to experiences from an actual multi-unit North American coal generating station. This flexibility requires limited modifications to hardware, but extensive modifications to operational practice.

Overview of Variable Renewable Energy Regulatory Issues: A Clean Energy Regulators Initiative Report. May 2014.
This CERI report surveys key regulatory issues associated with the deployment of renewable energy, particularly variable renewable energy (VRE) sources such wind and solar power. The report draws upon the research and experiences from various international contexts, and identifies key ideas that have emerged from the growing body of VRE deployment experience and regulatory knowledge. Research Highlights fact sheet.

Peer-to-Peer Consultations: Ancillary Services Peer Exchange with India: Experience from South Africa, Europe & the United States. May 2014.
In March 2014, the Power Partnership and the Regulatory Assistance Project - India hosted two peer-to-peer exchanges among experts from India, South Africa, Europe, and the United States to discuss the provision of ancillary services, particularly in the context of added variability and uncertainty from renewable energy. This fact sheet summarizes the consultation.

Flexibility in 21st Century Power Systems. May 2014.
Flexibility of operation—the ability of a power system to respond to change in demand and supply—is a characteristic of all power systems. Flexibility is especially prized in twenty-first century power systems, with higher levels of grid-connected variable renewable energy (primarily, wind and solar). Research Highlights fact sheet.

The Evolving Role of the Power Sector Regulator: A Clean Energy Regulators Initiative Report. April 2014.
This report seeks to briefly characterize the evolving role of the power sector regulator. It describes seven existing objectives of power sector regulators and nine emerging objectives, highlighting key challenges and outlining interdependencies. As the preliminary installment in a series, it aims to lay the groundwork for subsequent reports and case studies that will explore these topics in depth.

The Role of Demand Management in the Utility of the Future. April 2014.
Demand management and distributed generation could transform how consumers interact with the electricity grid and manage energy. Energy consumers may be shifting to view themselves as both consumers and increasingly as suppliers - with renewable energy generation on-site and demand response capability. This new consumer model and the concept of a distributed energy system may be disruptive to the traditional utility model. It also changes the operation and management of the U.S. electricity grid. The Institute for Building Efficiency and the 21st Century Power Partnership hosted a Roundtable Dialogue on how utilities of the future can adapt to capture the greatest benefits for consumers and utilities without adversely impacting reliability, price, and power availability.

Flexible Coal: Evolution from Baseload to Peaking Plant. December 2013.
Twenty-first century power systems, with higher penetration levels of low-carbon energy, smart grids, and other emerging technologies, will favor resources that have low marginal costs and provide system flexibility (e.g., the ability to cycle on and off to follow changes in variable renewable energy plant output). Questions remain about both the fate of coal plants in this scenario and whether they can cost-effectively continue to operate if they cycle routinely. The experience from the CGS plant demonstrates that coal plants can become flexible resources.

Market Evolution: Wholesale Electricity Market Design for 21st Century Power Systems. October 2013.
This report reviews the suite of wholesale power market designs in use and under consideration to ensure adequacy, security, and flexibility in a landscape of significant variable renewable energy. It also examines considerations needed to ensure that wholesale market designs are inclusive of emerging technologies, such as demand response, distributed generation, and storage.

Accelerating the Global Transformation to 21st Century Power Systems. The Electricity Journal. Volume 26, Issue 6, July 2013.
This report explains that nations and regions need to share lessons about the best ways to create enabling policies, regulations, and markets that get the most social benefit out of power systems and incent the necessary investments.

Integrating Variable Renewable Energy in Electric Power Markets: Best Practices from International Experience (Research Highlights)
This fact sheet highlights a 2012 report on best practices to enable variable renewable energy grid integration. The report studies cases from Australia (South Australia), Denmark, Germany, Ireland, Spain, and the United States (Colorado and Texas), which have effectively integrated variable RE utilizing diverse approaches.


Big, Fast, and Flexible: Grid Operations for Efficient Variable Renewable Integration
11 October 2016
Following a brief introduction to the basics of power system operations and power system flexibility, the webinar presents various methods and examples of pathways for moving towards larger balancing areas and faster dispatch under different institutional contexts.

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Clean Restructuring: Design for Low Carbon Wholesale Markets and Beyond
30 June 2016
The webinar will review three main areas of consideration for decision makers embarking on a clean restructuring process: planning and procurement, market operation rules, and network expansion and grid code. The webinar, based on the Power Partnership report features case studies of clean restructuring for Mexico, Denmark, and Germany, and the webinar will focus on current clean restructuring efforts in Mexico by the co-authors of the case study, Hector Beltran and Jose Maria Valenzuela.

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Greening the Grid: Implementing Wind and Solar Power Forecasting
21 April 2016
This webinar introduces the considerations associated with advancing the use of wind and solar forecasts to more efficiently integrate variable renewable energy into the grid. Discussion topics included how wind and solar forecasting enhance power system operations; how wind and solar forecasts are produced; approaches to structuring forecasting programs and the collection of necessary data; and policy and other actions to support forecasting.

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Greening the Grid: Implementing Renewable Energy Zones
1 December 2015
This webinar introduces the renewable energy zone (REZ) approach, including the value of REZ to a power system, crucial components of the REZ process, technical approach to defining REZs using geospatial analysis, and case studies to highlight examples and key lessons for implementing REZ in other parts of the world.

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Greening the Grid: Best Practices in Conducting Grid Integration Studies
6 October 2015
This webinar was presented as part launch of, which is designed to support countries in integrating renewable energy into the power system. It addresses fundamental questions, about conducting grid integration studies, best practices for engaging key stakeholders in them and the kinds of analysis and data that are involved in them. It includes several case studies to highlight lessons learned.

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Integrating Variable Renewable Energy into the Grid: Key Issues and Emerging Solutions
29 July 2015
This webinar reviews the challenges to integrating significant quantities of variable renewable energy to the grid as well as the emerging solutions that policymakers, regulators and grid operators have taken to integrate wind and solar and meet renewable energy targets. Webinar participants learn about the myths, misperceptions, costs and options for scaling up grid-connected renewable energy, as well as the Greening the Grid website and technical assistance opportunities.

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CERI Webinar: Experience in Europe with Support Schemes
8 April 2014
This webinar provided an overview of renewable electricity support schemes currently applied in Europe. Corinna Klessmann presented best practices, trends and challenges in renewable energy policy design, based on recent assignments for the European Commission.

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CERI Webinar: Incentives
25 March 2014
This webinar reviewed various incentives globally that have been adopted to attract clean and renewable energy projects and make them financially viable and attractive to private sector investors. The program included a review of different mechanisms, such as feed-in tariffs, RFP and procurement strategies, investment tax credits, priority dispatch, and other strategies.

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CERI Webinar: Regulatory Guidelines to Set Up Voltage Quality Monitoring
13 February 2014
This presentation assessed the issue of what regulators need to consider whenever establishing a voltage quality regulatory framework for distribution networks (i.e. up to 35 kV). It presented a general set of guidelines that regulators could consider in introducing and developing voltage quality regulation.

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CERI Webinar: Asset Management — Replacement Criteria for Distribution Transformers
16 January 2014
This session focused on asset management and distribution transformers, which are often regarded as commodities. They are relatively inexpensive and can be delivered off stock. Therefore alternatives for replacement need to be low cost, and thereby effective, efficient, and standardized.

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CERI Webinar: Analysis of Electricity Tariffs in Africa
6 January 2014
This session aimed to review electricity tariff structures in Africa, assess tariffs in terms of long-term financial viability for the electricity sector and ability to attract capital, and offer suggestions to evolve to a healthier and more attractive tariff structure.

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CERI Webinar: Regulatory Incentives for Reduction of Network Losses
9 December 2013
This webinar evaluates the incentives for investments in low-loss equipment in differing regulatory settings and outlines pathways to assure the proper embedding of these incentives.

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CERI Webinar: Clean Energy and the Role for Regulators
3 December 2013
This session focused on how the role of the regulator is defined, the differences in legal mandates for regulators in different jurisdictions, and the trade-offs regulators need to make in balancing the various, often competing, objectives set out in statute.

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Open Source Energy System Modelling with OSeMOSYS
In this webinar, panelists discuss energy modelling using OSeMOSYS, a fully fledged systems optimization model for long-term energy planning that is a simple, powerful, and transparent tool for informing the development of local, national and multi-regional energy strategies.

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CERI Webinar: Investment Incentives
11 November 2013
This session focused on the regulatory treatment of investments and incentives for investments. Finding an adequate balance between efficient and sufficient investments is one of the major tasks for regulators. They can use various approaches to assess and encourage investments necessary to provide reliable and efficient services. This session explained the types of investments and their integration in the regulatory price control.

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CERI Webinar: Role of Efficiency Analysis
4 November 2013
Regulatory authorities use different efficiency assessment methods to support the setting of efficiency increase targets for the regulated service providers. This session described the principles of this regulatory benchmarking.

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CERI Webinar: Principles of Price Regulation
28 October 2013
This session explained the nature of economic regulation and discussed the central question of why some parts of the electricity value chain remain regulated and are not subject to competition.

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