HPP: Hybrid Power Plants

Objectives

This Task addresses key research questions related to the design, operation, and large-scale deployment of hybrid power plants (HPPs), integrating wind, solar, storage, and other technologies. The central questions are: (1) What capabilities should hybrid power plants deliver (e.g., dispatchability, grid services), and what combinations of technologies and storage solutions are required to achieve them? (2) Which modeling, optimization, and control tools are necessary to maximize system value, reduce costs, and enable optimal siting and operation? (3) What electrical design configurations and infrastructure concepts best support flexibility, shared resources, and reliable grid integration?

These questions are critical as renewable energy resources take on a broader role, delivering not only energy but also the reliability, flexibility, and market services needed to support a modern power system. As renewable penetration increases, variability and uncertainty limit the ability of standalone wind and solar plants to participate fully in electricity markets and grid support functions. Hybridization offers a pathway to overcome these limitations, but introduces new complexities in system design, control, forecasting, and market participation.

Addressing these research questions is essential to unlock the full value of hybrid power plants, reduce investment risks, and accelerate their deployment globally. The outcomes will provide guidance on best practices, identify barriers to adoption, and support the development of standards, tools, and roadmaps needed by industry, regulators, and researchers to enable a reliable, cost-effective, and sustainable energy transition.

Participation

Additionally, Task 50 includes Observers from Australia, Austria, France, UK, Spain, Sweden, India, China.

Progress, Results, and Impact in 2025

The activities across the work packages are delivering tangible progress toward advancing the understanding, design, and deployment of hybrid power plants (HPPs). Through collaborative research, open data sharing, and engagement with the international research and industry community, the project is generating knowledge and tools that support stakeholders working to integrate wind, solar, storage, and other technologies into coordinated energy systems. These efforts contribute to broader societal goals by enabling more reliable and flexible renewable energy systems, supporting decarbonization, and helping accelerate the transition to low-carbon power systems.

Results from the project are being disseminated through peer-reviewed publications, conference presentations, open-source repositories, and international workshops. These communication activities ensure that project outcomes are accessible to researchers, industry practitioners, and policymakers, allowing the results to inform future hybrid plant development, system planning, and modeling practices. By developing shared definitions, reference designs, and benchmarking studies, the work supports alignment across organizations and provides practical resources that can be used by industry and research groups working on hybrid energy systems.

Work Package 1 – Establishing a shared definition and terminology for hybrid power plants.

We are currently finalizing a journal for submission to Applied Energy that presents and disseminates the final outputs of Work Package 1, including: (1) a finalized HPP definition, (2) a comprehensive list of associated sub-terms, (3) supporting graphics, and (4) a decision-tree matrix. Additionally, an abstract has been submitted and accepted for a presentation at the 10th International Hybrid Power Plants & Hybrid Energy Systems Workshop. This would mark the first formal presentation of the finalized Work Package 1 outputs to the broader hybridization community.

Work Package 2 – Developing a first open reference design for hybrid power plants.

WP2 focused on the detailed description of a first reference design for HPPs, using high-level design parameters decided with HyDesign (DTU). Participants at NLR (former NREL), TU Delft, Engie Laborelec and Reutlinger university designed the wind farm and cable layout, the solar PV farm, battery and electrical infrastructure. A first version of the full design has been published open-source on a github repository (https://github.com/IEAWindTask50/hpp-reference-designs), using the windIO format developed by Task 55. A manuscript describing the design has been drafted, to be published as a data description article by the end of 2026. The writing effort is led by TU Delft and DTU, with co-authors from additional five organizations.

Work Package 3 – Benchmarking modeling tools used to design and evaluate hybrid plants.

WP3 has focused on the benchmarking study for H2Integrate (NLR; formerly HOPP) and HyDesign (DTU), which considers six locations, three each in Europe and North America. Preliminary results for a site in Texas were presented at the Wind Energy Systems Conference in 2025, with overall good agreement but several discrepancies noted. The focus of the work since then has been on resolving discrepancies and adding additional sites, which are still underway. We believe that the opportunity for the benchmarking exercise to facilitate collaboration remains promising. In recent months, information are being collected about other promising codes and sources of data that may further the collaboration possibilities.

WP4 – Electrical design, control, market and grid service provision from hybrid power plant

Significant progress has been made in developing the deliverable on an open-source model for utility-scale hybrid power plant (HPP) control. The work focuses on defining a generic control architecture, system characterization, and key control functionalities to enable coordinated operation of wind, solar, and storage technologies. Initial results include the formulation of control levels, operational modes, and grid service capabilities such as frequency response and ancillary services. The work also addresses challenges related to diverse electrical topologies and integration strategies. This ongoing effort aims to establish a standardized, flexible modeling framework to support validation, interoperability, and future development of HPP control solutions.

Next Steps

• We are wrapping up Phase 1 and preparing to continue in Phase 2. Phase 2 is officially kicked-off in April 2026. Phase 2 will extend Phase 1 by addressing gaps, refining methods, and enhancing deliverables using accumulated expertise. Efforts will coordinate international R&D on hybrid wind-based plants integrating wind, solar PV, energy storage, and power-to-X in collaboration with Task 61. Key scopes include –
• Extend Phase 1 work to address gaps, refine methods, and enhance deliverables, leveraging accumulated expertise.
• Coordinate international R&D on hybrid wind-based power plants integrating wind, solar PV, energy storage, and/or power-to-X (in collaboration with Task 61).
• Deliver harmonized taxonomy, validated models, reference controls, test methods, and standards.