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The 21st Century Power Partnership (21CPP) publications 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.

Thought Leadership Publications »

Thought Leadership Publications provide information about and analysis of market design and regulatory issues for clean energy and 21st century power systems.

Featured Publications

Lessons Learned for Rapid Decarbonization of Power Sectors

September 2022
This report covers key lessons learned for the rapid decarbonization of power sectors, emphasizing best practices in planning, building, and operating electricity systems. Decarbonization covers all greenhouse gases, including carbon dioxide and methane. The intended audience of this report consists of energy ministers and other high-level energy sector decision makers.

Lessons Learned for Rapid Decarbonization of Power Sectors: Key Lessons for Energy Ministers
(Two-Page Fact Sheet)

September 2022
This report covers key lessons learned for the rapid decarbonization of power systems, emphasizing best practices in planning, building, and operating power systems. This report is the result of a collaborative effort among various Clean Energy Ministerial (CEM) workstreams and partner initiatives. The contents are not intended to be comprehensive of all power sector topics, and there may be overlap between content in each section due to the nature of this first-of-its-kind collaborative effort to deliver unified messaging on power sector decarbonization to energy ministers. This work is intended to complement other work at the CEM and offers options for consideration, not specific policy recommendations.

Clean Grid Vision: A U.S. Perspective

September 2021
This report aims to present perspectives on the main issues in future grid development, covering both supply and demand. It focuses on the lessons learned through the National Renewable Energy Laboratory and the 21st Century Power Partnership Initiative's studies of the U.S. power sector that have measured the impacts of high-penetration variable renewable energy and tested strategies for enhancing grid flexibility and reliability. As such, this report is limited in its scope and does not attempt to review or summarize all power system literature. Although it refers to relevant external literature to provide context when needed, this study is primarily a summary of the National Renewable Energy Laboratory and the Century Power Partnership Initiative's research over the past five years on five topics, which each correspond to the five chapters in the report.

Other Publications

Transmission Planning With Renewable Energy Zones (REZ): Overview, Select Case Studies, and Key Enablers

March 2023
The REZ transmission planning process is a proactive method to plan, approve, and build transmission infrastructure that connects high-quality and large-scale renewable resources to the power system. This presentation was developed for a technical side event focused on transmission systems to facilitate the rapid decarbonization of power systems at the Clean Energy Ministerial Senior Officials Meeting in March 2023. This document contains a synthesis of key REZ case studies throughout the world and is intended as a resource for policymakers and energy planners.

Experiences from the Power System Flexibility Campaign

September 2022
This publication highlights policy findings and experiences in implementing CEM workstreams during the Power System Flexibility Campaign.

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.

Country-Level Publications

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Brazil joined 21CPP in mid-2017, and dialogue is currently underway on priorities for collaboration.

Featured Presentations

Capacity Value of Variable Renewable Energy (VRE) Resources

May 2018
This webinar focused on the use of capacity expansion models in long-term planning and how they ensure "enough" capacity is built if significant quantities of variable renewable generation exist. NREL's capacity expansion model, ReEDS (Regional Energy Deployment System), is described. It also describes the concept of capacity value and different techniques used to quantify it .

Large-Scale Integration of Variable Renewable Energy: Key Issues and Emerging Trends

March 2018
This webinar summarized key lessons, trends and best practices associated with integrating utility-scale VRE into grids, with a special in-depth case study from India

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China »


Featured Publications

China Renewable Energy Outlook 2017

November 2017
This report focuses on China’s options for a low-carbon energy transition through 2050, and the short-term actions needed to remove obstacles for renewable energy development.

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India »


Featured Publications

Greening the Grid: Pathways To Integrate 175 Gigawatts of Renewable Energy into India's Electric Grid

June 2017
This study used specially designed weather and power system modeling to identify how India’s power system balances generation and demand throughout the year.

Read the overview to learn more.

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Mexico »


Featured Publications

Mexico Clean Energy Report

April 2022
Mexico is ideally positioned to become a clean energy powerhouse given its world-class renewable energy resource potential and the low cost of renewable energy generation. This report highlights how rapid growth in renewable energy deployment in Mexico could generate high levels of investment, increase energy access, reduce costs to consumers, and—together with other actions—improve the reliability and resilience of Mexico's power system.

Impacts Analysis of Amendments to Mexico's Unit Commitment and Dispatch Rules

January 2022
This report quantifies the potential impacts on Mexico's power systems of amendments both published and under discussion to Mexico's electricity legal framework, along with market rules that would modify the way electricity generators are committed and dispatched.

A Report on the Implementation of Smart Grids in Mexico

January 2019
This report presents a compilation of data and information from many sources that document Mexico’s progress in implementing a Smart Grid as part of ongoing efforts to transform its electric power industry.

Baja California Sur Renewable Integration Study

November 2018
The goal of the Baja California Sur (BCS) Renewable Integration Study is to evaluate the potential impacts of increasing penetration levels of wind and solar power on BCS’s bulk power system operations for the year 2024, which is the year Mexico has set the goal of reaching 35% of total electricity generation clean energy sources.

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South Africa »


Featured Publications

Preliminary Findings of the South Africa Power System Capacity Expansion and Operational Model Study

January 2018
This state-of-the-art grid integration study examined the effects of potential high penetrations of variable renewable energy on South Africa’s power system. To achieve this, NREL developed, tested, and ran a combined capacity expansion and operational model of the South African power system including spatially disaggregated detail and geographical representation of system resources. New software to visualize and interpret modelling outputs was developed, and scenario analysis of stepwise variable renewable energy build targets provides new insight into associated planning and operational impacts and costs.

21st Century Power Partnership: September 2016 Fellowship Report

September 2017
This Fellowship is a follow-up to the “Technical Audit of Eskom’s Medium- and Long-term Modelling Capabilities,” conducted by the National Renewable Energy Laboratory (NREL) in April 2016. The prospect and role of variable renewable energy (vRE) in South Africa poses new modelling-related challenges that Eskom is actively working to address by improving the fidelity of PLEXOS LT and ST models.