Los Alamos National Laboratory Advanced Simulation and Computing (ASC) Program
Ensuring the safety and reliability of the nation's nuclear weapons stockpile

Los Alamos site enables next generation supercomputing

Favorable climate, ample power, and development potential make Los Alamos the ideal location for future supercomputing


  • FOUS Program Manager
  • Jason Hick
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TA3 aerial

Technical Area 3 (TA-3) is home to the Laboratory’s main administrative buildings, several research facilities, and the Strategic Computing Complex. Just beyond TA-3 is Two Mile Mesa. The WTA Substation is visible in the upper right of the photograph.

As the nation moves further from the nuclear test base, computer simulations are becoming an increasingly important part of national security. The National Nuclear Security Administration’s Advanced Simulation and Computing (ASC) program relies on computer simulations to assess, predict, and certify the safety, reliability, and performance of the nation’s nuclear stockpile.

To solve these complex problems, Los Alamos National Laboratory (LANL) employs some of the world’s most powerful supercomputers. High fidelity, three dimensional simulations reveal details not observable through experimentation alone. To produce the highest fidelity results possible, LANL is pursuing higher density computing systems—exascale systems and new architectures providing high efficiency. The breadth and depth of such computing will put enormous demand on high performance computing (HPC) facilities.

As supercomputing systems evolve, so too must facilities evolve. If history is any indication of the future, power and cooling will determine capability. Future facilities must deliver the requisite power reliably and sustainably, and they must provide cooling to match. Los Alamos—with favorable climate, ample power, and available land—is the ideal place for future supercomputing capability.

Los Alamos has an ideal climate for supercomputing

Situated 7,500 feet above sea level on the eastern slopes of the Jemez Mountains, Los Alamos offers an ideal climate for efficient high performance computing facilities. The high mountain air is cool and dry. The year round average temperature in Los Alamos is ~48°F (See Figure 1). The daily mean temperature in July, the hottest month of the year, is just ~68°F, and the wet bulb temperature stays below 70°F for 94% of the year.

These low temperatures are ideal for free air cooling. A free air cooling system takes advantage of the cool temperatures by pulling the outside air into the building. Inside the building, the cooler air sinks and pushes the warmer air upward, drawing heat away from computer hardware. The building then allows the warmer air to escape.

Free air cooling is the most energy efficient and sustainable cooling option. It uses zero water and minimal electrical power (to run fans). It is the most efficient and sustainable cooling system, but only where and when the environment allows. At Los Alamos, free air cooling would work most of the year.

During the short time of year when free air cooling is insufficient, the dry climate is ideal for evaporative cooling—transferring heat to the air simply by evaporating water. Evaporative coolers, by definition, require a continual flow of water. Dry coolers are capable of efficiently cooling without the need for continual water. Dry coolers draw cool air (relative to computer hardware) through an adiabatic pad to further cool the air. The cooler air cools a closed-loop of fluid that can then be pumped to cool computer hardware.

The combination of free air and dry cooling provides an energy efficient and sustainable way to cool supercomputers. Los Alamos provides a climate amenable to both.

tempertaures in Los Alamos

Ample power for future supercomputing

For any supercomputing facility, power is a key driver of capability. Electrical power correlates strongly to computational power. With each new ASC system, new science simulation demands computational power increases.

To plan for future power requirements, LANL has a detailed strategy that balances mission need, cost, risk, known market conditions, operational goals, and environmental concerns. Over the next decade, LANL will continue to develop a broad energy portfolio. Multiple energy sources will combine to provide the power required to carry out the mission, and the diversity of sources will also improve the Laboratory’s energy security.

Sustainability is an integral part of the Laboratory’s mission to meet the nation’s scientific challenges. LANL is implementing sustainable solutions as a regular part of doing business. The Laboratory is exploring future plans that include a small modular reactor, a more efficient Combined Heat and Power Plant, and a photovoltaic plant.

Early assessments were recently completed for a ground-mounted, 10-MW photovoltaic plant. To identify the most desirable location, the Laboratory conducted a detailed analysis of the entire campus. Assorted environmental, historical, and cultural resources posed some constraints, but with almost 35 square miles of land, numerous options existed. In this instance, the proposed site for the photovoltaic plant is optimally located for maximum solar exposure and near the WTA substation complex.

When identifying locations for a supercomputing facility, access to power becomes a chief consideration. One way to maximize power and efficiency is to co-locate a facility as close as possible to the power supply. Locating near a substation does two things. It minimizes power lost during distribution from substation to facility, and it reduces cost by eliminating the need for long distribution lines from substation to facility.

Site ready for development

In anticipation of future supercomputing needs, Los Alamos has recently conducted a study to identify possible locations for development. The study took into account power and cooling resources as well as environmental, wildlife, traffic, cultural, and other potential impacts. The Laboratory’s 35 sq. mile campus offered several options, but one location stood out above others: Two Mile Mesa.

Two Mile Mesa is just south of the Laboratory’s main technical area and home to one of its electrical substations. The land immediately surrounding the substation is undeveloped. The specific site identified is not only close to the substation, it shares a site boundary. Distribution lines from the substation to the site would be minimal—less than 500 feet. This could save tens of millions of dollars in the cost of transmitting power and make growth cheaper and easier.

Development in this section of the Laboratory also presents opportunities to take advantage of the latest facility technology for more efficient and sustainable cooling. It would open the door for free air cooling technology and provide the space needed for dry coolers. This combination could reduce the Laboratory’s overall water consumption.

Two Mile Mesa also offers room for future capabilities. Should the need arise for additional computing capabilities, staging facilities, supporting office space, or a centralized supercomputing campus, Two Mile Mesa can meet the requirements. In fact, the study found that the site could support supercomputing capabilities 40 years into the future.

Looking to the future

To support the high fidelity simulations needed to fulfill its mission, ASC will rely on high density computing systems. These future systems will place increased power and cooling demand on facilities.

Los Alamos is prepared to meet the demands of the future with efficient and sustainable solutions. Diverse and renewable energy sources will deliver the necessary power reliably and sustainably. Free air cooling and dry cooling technology will reduce power and water consumption. Two Mile Mesa enables these goals and is ready for development.