Breakthrough Science at Every Scale 

Simulation is a vital part of the research process, joining theory and experiment to form the three 

pillars of science. With simulation, researchers have the ability to study extreme-scale phenomena 

such as climate cycles all the way down to the most microscopic of materials. The Oak Ridge 

Leadership Computing Facility (OLCF) at Oak Ridge National Laboratory is one of the most 

powerful high-performance computing (HPC) centers in the world, providing researchers 

working on some of the most challenging problems of the 21st century with leadership-class 

computers for scientific simulations. 

These HPC systems—supercomputers—enable a level of detailed analysis unavailable through 

traditional experimental or theoretical means. Coupled with the expertise of the OLCF technical 

staff, supercomputers such as the ones at the OLCF afford scientists new opportunities to study 

subatomic particle interactions, simulate the volatile conditions inside a combustion or turbine 

engine, develop new treatments for diseases, design materials that can revolutionize industries,

and model the origins of the universe.

Supercomputers for Speedy Solutions

The OLCF is home to the nation’s fastest supercomputer, Summit, an IBM AC922 system that 

debuted in 2018. Summit has a theoretical peak performance of 200 petaflops, meaning the system 

can solve 200 quadrillion calculations per second. Summit is about eight times more powerful than 

its predecessor, the OLCF’s previous 27-petaflop Titan supercomputer. 

With Summit and other HPC resources at the OLCF, scientists can employ more precise calculations 

and develop increasingly complex models, leading to high-fidelity solutions. In 2018, researchers 

broke the exascale barrier on Summit with a genomics algorithm, achieving a peak throughput of 

2.36 exaops—or 2.36 billion billion reduced precision calculations per second, the fastest science 

application ever reported. The next chapter in the OLCF’s legacy is taking shape in the form of 

Frontier, which is slated to be the nation’s first exascale system with a sustained speed of greater 

than 1.5 exaflops when it comes online for early users in 2022.

“To draw scientific conclusions in our work related to COVID-19, 

we need to run many molecular dynamics simulations and generate 

an enormous amount of data. Summit provides the immense 

compute power to handle that workload.”

 John Gounley, Summit User

 and Computational Scientist, ORNL

Oak Ridge Leadership

Computing Facility 

OAK RIDGE NATIONAL LABORATORY

250

petabytes

Capacity of the

OLCF’s disk storage

system

174 

US institutions that used

the OLCF in FY 2021,

including universities,

companies, and

government 

agencies 

1,696 

Researchers who

worked with the 

OLCF in 2021

119 

OLCF publication

citations since

2021

392

Average OLCF 

publications per year 

from 2012–2021 by

OLCF staff and 

users

657

Unique OLCF

computing

projects 

in 2021 
Recent Impacts

Industrial competitiveness—General Electric uses Summit to simulate combustion in gas-powered turbines. By using 

computer simulations, researchers get more designs to evaluate, allowing them to make leaps in turbine efficiency that 

translate to millions of dollars in saved fuel and millions of tons of reduced carbon pollution.

Energy-efficient materials—A team at Lawrence Berkeley National Laboratory is using Summit to study copper-based 

superconductors to understand the interactions between the particles in these materials. Superconductors have zero electrical resistance when they reach sufficiently low temperatures and are being explored for technologies such as magnets for 

MRIs, fusion devices, and particle accelerators.

Understanding COVID-19—Researchers at Argonne National Laboratory have used Summit to simulate the SARS-CoV-2 

virus’ spike protein in numerous environments, including within the SARS-CoV-2 viral envelope comprising 305 million 

atoms—the most comprehensive simulation of the COVID-19–causing virus performed to date. The results have led to 

discoveries of one of the mechanisms the virus uses to evade detection as well as a characterization of interactions between 

the spike protein and the protein that the virus takes advantage of in human cells.

Summit by the Numbers

CONTACT:

Gina Tourassi

Director

National Center for 

Computational Sciences

tourassig@ornl.gov,

865-576-4829

One Bethel Valley Road, 

Oak Ridge, TN 37830

www.ornl.gov

Oak Ridge National Laboratory is managed by UT-Battelle LLC for the US Department of Energy January 2022

200 petaflops If everyone on Earth made one calculation per second, it would take more 

than 300 days to do what Summit can do in 1 second.

8.8 megawatts Summit is very efficient, demonstrating a sustained performance of 

122.3 petaflops using just 8.8 megawatts of power.

4,000 gallons The amount of chilled water circulated through Summit every minute. 

5,600 square feet Summit’s footprint is about as big as two tennis courts.