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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 View All Thought Leadership Publications »

Featured Publications

Status of Power System Transformation 2018: Advanced Power Plant Flexibility

May 2018
The report is aimed at policy makers and regulators who are not experts in engineering, but who need to understand power plant flexibility in order to enhance system planning and upgrade policy, market and regulatory frameworks.

Next-Generation Performance-Based Regulation: Emphasizing Utility Performance to Unleash Power Sector Innovation

May 2018 (Update)
We have re-organized the original report into a new 3-volume series, which you can read here:

Other Publications

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.

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Accelerating the Global Transformation to 21st Century Power Systems

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.

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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 .

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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 View All China-Related Publications »

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 View All India-Related Publications »

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 View All Mexico-Related Publications »

Featured Publications

First Steps in the Smart Grid Framework:  An Optimal and Feasible Pathway Toward Power System Reform in Mexico

June 2018
This report describes for Mexico’s Ministry of Energy (SENER) an overall approach (Optimal Feasible Pathway) for moving forward with smart grid policy development in Mexico to enable increasing electric generation from renewable energy in a way that optimizes system stability and reliability in an efficient and cost-effective manner.

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The Status and Outlook of Distributed Generation Public Policy in Mexico

May 2018
This report summarizes the current status of distributed generation markets, laws, and regulations in Mexico to provide readers with a common foundation of knowledge to support Mexico’s public policy development. This includes an explanation of core distributed generation issues, opportunities, and prospects for Mexico.

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South Africa View All South Africa-Related Publications »

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.

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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.

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