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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.

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Featured Publications

Electric Vehicle and Power System Integration: Key Insights and Policy Messages from Four CEM Workstreams

September 2020
This report summarizes how key stakeholders and policies can ease the integration of rapidly growing EVs and their interaction with the power grids upon which they depend for charging. The report is the result of a deliberate collaboration between four CEM workstreams: 21st Century Power Partnership Initiative (21CPP), Electric Vehicles Initiative (EVI), International Smart Grid Action Network initiative (ISGAN) and Power System Flexibility campaign (PSF). Included are policy messages based on current experience, with a particular focus on the role of critical stakeholders in a transformation that crosses multiple sectors. Many of these findings emerged from a highly interactive virtual workshop held on 19-20 April 2020, which engaged approximately 75 international experts from 18 countries and diverse backgrounds.

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Status of Power System Transformation 2019: Power System Flexibility

May 2019
As power systems around the world transform, power system flexibility has become a global priority. A range of operational, policy and investment-based interventions are available to render modern systems more flexible, thereby facilitating cleaner, and more reliable, more resilient, and more affordable energy. This report identifies challenges and opportunities to unlock system flexibility and accelerate power system transformation (PST) efforts. It provides an overview of the policy, regulatory and market instruments which can be implemented in different power sector contexts to mitigate these challenges.

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Innovative Utility Offerings at the Distribution Edge: Case Studies from Around the Globe

May 2019
This report catalogues several innovative approaches utilities are taking to meet consumer preferences in a fast-changing world. It comprises a series of case studies for products and programs that enhance the consumer experience, provide greater access to distributed energy resources, and generally respond to the changing realities of the utility/customer relationship.

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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

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.

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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 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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