Call for Proposals

Information

The ASCR Leadership Computing Challenge (ALCC) is a high performance computing allocation program for projects of interest to the Department of Energy (DOE), with an emphasis on high-risk, high-payoff scientific campaigns in areas directly related to the DOE mission, that respond to national emergencies, or that broaden the community of researchers capable of using leadership computing resources.  ALCC projects span a wide range of large-scale computing approaches, including modeling and simulation, artificial intelligence (AI), and data analysis.

ALCC is currently soliciting proposals for allocation awards for the 2026-2027 allocation year. The high performance computing (HPC) platforms available for the current allocation cycle include Frontier, the exascale system at the Oak Ridge Leadership Computing Facility (OLCF); Aurora, the exascale system at the Argonne Leadership Computing Facility (ALCF); Polaris, a 44-petaflop accelerated system at ALCF; and Perlmutter, an accelerated system at the National Energy Research Scientific Computing Center (NERSC). 10% to 30% of the allocatable computing time will be made available on each of these machines to the ALCC program.

New Information:

• Single-step Submission: The ALCC proposal submission process will feature a single proposal submission (i.e. no pre-proposal submission).
• Multi-year Awards: ALCC will now accommodate multi-year proposal requests. Applicants can request computation time for up to three years. If granted an allocation, a renewal proposal will need to be submitted to access subsequent year(s) allocations.
• Mid-year Allocation Reductions: On November 1, 2026 and March 1, 2027, a percentage of unused allocation hours will be returned to the ALCC program for redistribution to other projects. For more information, please see Allocation Reduction Information.

Overview:

Open to scientists from the research community in industry, academia, and national laboratories, the ALCC program allocates from 10% to 30% of the computational resources at ASCR’s three high performance computing facilities: NERSC at Lawrence Berkeley National Laboratory and the Leadership Computing Facilities at Argonne and Oak Ridge National Laboratories. These resources represent some of the world’s fastest and most powerful supercomputers.

ALCC is one of several allocation programs for ASCR supercomputing facilities (see ASCR Allocation Policy) and supports ASCR’s efforts to further DOE mission science, respond to National emergencies, or to broaden community access to leadership computing facilities. To fulfill its goal of broadening community access, ALCC supports a range of project allocation sizes and allocates time across all three ASCR supercomputing facilities. However, proposals seeking very large allocations are more appropriate for the INCITE allocation program. Projects that request more than the maximum request limit will be considered nonresponsive and may be declined without review.

The ALCC program has a strong legacy of advancing scientific discovery and innovation across a wide range of DOE mission applications, including energy efficient engineering, computer science, materials and chemical sciences, geosciences and energy-related biosciences, biological and environmental sciences, computational fluid dynamics, high energy and nuclear physics, fusion sciences, cosmology, the design and control of scientific user facilities and experiments at these facilities, nuclear energy, fossil energy and renewable energy (see ALCC Past Awards and FAQ Detail).

ALCC Resources

ALCC allocates high performance computing time on the primary HPC machines at each ASCR facility. For the 2026-2027 ALCC allocation year, these resources include the following estimated hours:

• 20,000,000 node-hours on Frontier at Oak Ridge Leadership Computing Facility,
• 16,000,000 node-hours on Aurora at Argonne Leadership Computing Facility
• 1,000,000 node-hours on Polaris at Argonne Leadership Computing Facility,
• 2,250,000 CPU-node-hours on Perlmutter at National Energy Research Scientific Computing Center (for use on Perlmutter's CPU-only nodes), and
• 1,250,000 GPU-accelerated node-hours on Perlmutter at National Energy Research Scientific Computing Center (for use on Perlmutter's GPU-only nodes).

For a description of the computing resources at ASCR facilities, please see:

• National Energy Research Scientific Computing Center (NERSC): https://www.nersc.gov/systems
• Argonne Leadership Computing Facility (ALCF): https://www.alcf.anl.gov/computing-resources
• Oak Ridge Leadership Computing Facility (OLCF): https://www.olcf.ornl.gov/olcf-resources

ALCC Proposal Submission

The ALCC proposal submission process is now a one-part application consisting of a proposal submission. For more information about the proposal, please see the proposal submission information page.

Selection

Awards are granted based on the quality of research, responsiveness to DOE and National priorities, and computational merit. Proposals undergo an external peer-review and assessment by computational experts at ALCF, OLCF, and NERSC. Selections are made by an internal ALCC Working Group which consists of the ALCC Program Manager and Program Managers from across the DOE as well as ASCR Leadership.  

Current Awards

ALCC issues allocation awards that are active from July 1 to June 30 of the following calendar year. For a listing of 2025-2026 awarded projects see Current Awards. For awards from previous years see Past Awards.

See side bar for more ALCC information links.