Energy Systems

, Volume 7, Issue 2, pp 297–332 | Cite as

Co-optimization of electricity transmission and generation resources for planning and policy analysis: review of concepts and modeling approaches

  • Venkat Krishnan
  • Jonathan Ho
  • Benjamin F. Hobbs
  • Andrew L. Liu
  • James D. McCalley
  • Mohammad Shahidehpour
  • Qipeng P. Zheng
Original Paper


The recognition of transmission’s interaction with other resources has motivated the development of co-optimization methods to optimize transmission investment while simultaneously considering tradeoffs with investments in electricity supply, demand, and storage resources. For a given set of constraints, co-optimized planning models provide solutions that have lower costs than solutions obtained from decoupled optimization (transmission-only, generation-only, or iterations between them). This paper describes co-optimization and provides an overview of approaches to co-optimizing transmission options, supply-side resources, demand-side resources, and natural gas pipelines. In particular, the paper provides an up-to-date assessment of the present and potential capabilities of existing co-optimization tools, and it discusses needs and challenges for developing advanced co-optimization models.


Co-optimization Transmission expansion planning Generation expansion planning Model fidelity Energy storage Demand response Integrated network uncertainty  Long-term planning AC and DC power flow 



The authors would like to acknowledge the National Association of Regulatory Utility Commissioners (NARUC) for supporting our efforts in writing the whitepaper on co-optimization [23]. The authors are also grateful to Bob Pauley, Doug Gotham, Stan Hadley, and Patrick Sullivan for their comments. Opinions expressed in this paper, however, as well as any errors or omissions, are the authors’ alone.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Venkat Krishnan
    • 1
    • 2
  • Jonathan Ho
    • 3
  • Benjamin F. Hobbs
    • 3
  • Andrew L. Liu
    • 4
  • James D. McCalley
    • 1
  • Mohammad Shahidehpour
    • 5
  • Qipeng P. Zheng
    • 6
  1. 1.Department of Electrical and Computer EngineeringIowa State UniversityAmesUSA
  2. 2.National Renewable Energy LaboratoryGoldenUSA
  3. 3.Department of Geography and Environmental EngineeringJohns Hopkins UniversityBaltimoreUSA
  4. 4.School of Industrial EngineeringPurdue UniversityWest LafayetteUSA
  5. 5.Electrical and Computer Engineering DepartmentIllinois Institute of TechnologyChicagoUSA
  6. 6.Department of Industrial Engineering and Management SystemsUniversity of Central FloridaFloridaUSA

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