FEDERAL ENERGY MANAGEMENT PROGRAM

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Energy Efficiency &

Renewable Energy

Energy Efficiency &

Renewable Energy

Sandia National Laboratories has developed extensive 

water efficiency improvements at its Microsystems and 

Engineering Sciences Applications (MESA) complex 

in Albuquerque, New Mexico. Since 1949, Sandia has 

developed science-based technologies that support 

national security: nuclear weapons, energy and infrastructure assurance, nonproliferation, defense systems and 

assessments, and homeland security. 

The laboratory sits on 8,699 acres of land and employs 

more than 10,000 employees and contractors. Altogether, 

it owns 871 buildings encompassing more than 5.8 

million square feet. 

The MESA complex houses research in microelectronics, 

including designing and prototyping microsystem-based 

components. The complex consumes about 28% of the 

total water used at Sandia. The processes used to create 

microelectronics systems require high-purity water for 

cleaning. 

Over the last several years, Sandia has initiated projects 

that have saved 80 million gallons annually, which 

represents 18% of the current water use at the laboratory. 

These savings were achieved by increasing the efficiency 

of the system, recycling higher-quality spent rinsewater, 

and reclaiming water to use for acid waste scrubbers and 

cooling towers. 

Much of Sandia’s success is due to proactively identifying 

conservation opportunities before plant upgrades 

are undertaken. That way, water conservation can be 

quickly included into new construction projects. After 

the upgrade is completed, a customer team takes over 

responsibility to find additional opportunities for 

reducing water consumption.

MICROELECTRONICS PLANT WATER EFFICIENCY 

IMPROVEMENTS AT SANDIA NATIONAL 

LABORATORIES

Best Management Practice 

Case Study #13 — Other Water Use

The U.S. Department of Energy’s (DOE) Federal Energy Management Program 

(FEMP) facilitates the Federal Government’s implementation of sound, costeffective energy management and investment practices to enhance the nation’s 

energy security and environmental stewardship.

Project Summary

High-Efficiency Reverse Osmosis

The MESA complex requires water with a high-purity 

level for its processes. This water goes through several 

pretreatment processes before being delivered to a reverseosmosis system. Water impurities are removed by sending 

the water under high pressure through a semi-permeable 

membrane that filters out dissolved minerals and pollutants. 

A traditional reverse osmosis system has a recovery rate of 

about 65%. In other words, for every 100 gallons of water 

entering a traditional system, it produces 65 gallons of 

pure water called “permeate” and 35 gallons of discharged 

wastewater called “concentrate”. 

PIX 16458

Holding tanks for the Sandia

water reclamation system.

PIX 16457

The HEROTM system consists of horizontal high-pressure 

pumps made of stainless steel that force spent water through 

a reverse osmosis membrane, which is inside the cylinder with 

the white housing.
For additional information 

please contact:

EERE Information Center

1-877-EERE-INF (1-877-337-3463)

www.eere.energy.gov/informationcenter

Printed with a renewable-source ink on paper 

containing at least 50% wastepaper, including 

10% post consumer waste.

Prepared by the National Renewable 

Energy Laboratory (NREL) a national 

laboratory of the U.S. Department of 

Energy Office of Energy Efficiency and 

Renewable Energy; NREL is operated by 

the Alliance for Sustainable Energy, LLC.

DOE/GO-102009-2905 • August 2009

Prepared by the National Renewable Energy Laboratory (NREL)

NREL is a national laboratory of the U.S. Department of Energy

Office of Energy Efficiency and Renewable Energy

Operated by the Alliance for Sustainable Energy, LLC

New version/bitmap logo/and outline type

Sandia upgraded the older water plant to a patented 

water treatment system, called High Efficiency Reverse 

Osmosis (HEROTM ). The HERO system pre-treats the feed 

water entering the system to remove calcium, magnesium, 

and silica from the water and raise the water’s pH level. 

Removing these minerals from the water reduces hardness and makes the water more alkaline. This increased 

alkalinity, in turn, reduces scaling on the reverse osmosis 

membrane and increases the recovery rate. With HERO, 

Sandia is able to recover 95% of the total water entering 

the system and rejects only 5%. In 2008, this increased 

efficiency resulted in savings of 34 million gallons of water.

Water Recycling

Sandia also recycles a portion of the spent rinse water 

from microelectronics cleaning at the MESA complex. 

There are multiple discharge water streams in the plant 

processes, and not all of them are suitable for reuse. With 

proper treatment, however, some of these spent water 

streams can be recycled back to clean microelectronics. 

MESA recycles approximately 6 million gallons of water 

annually in this manner. 

Water Reclamation

Water is also reclaimed from the microelectronics processes 

and is used in the system’s acid waste scrubbers and in 

nearby cooling towers. The water that is reclaimed from the 

system for these two applications is of lower quality than 

water that is selected for the recycle treatment. 

Domestic

potable

water

Treatment MESA

processes

Acid waste

neutralization

Reverse osmosis

 reject/

backwash

Recycle

treatment

Cooling

towers and

scrubbers

Sewer

Spent rinse water

Reclaim

Blow down

Scrubbers remove contaminants from the exhaust of the 

microelectronic processes. Reclaimed water is used for 

these scrubbers in place of potable water. Reclaimed water 

from the microelectronics plant is also used in cooling 

towers for makeup water. A portion of the spent water is 

pumped from the plant to three holding tanks. The storage 

tanks are connected to several cooling tower systems and 

reclaimed water is pumped to the cooling towers. There is 

an automatic system that uses city water as a back-up to 

the reclaimed water. Annually, Sandia reclaims 40 million 

gallons of water to be used in the acid waste scrubbers and 

the cooling towers. 

A simplified flow chart below shows the general path of the 

recycled and reclaimed water in the MESA plant.

Cost and Savings Summary

Using a “system engineering” approach that looks at all 

potential uses of water and that considers opportunities 

for reduction, recycling, and reclamation has resulted in 

significant water conservation opportunities for Sandia 

National Laboratories; these are summarized below:

	 •	 Through a higher efficiency reverse osmosis process,

the HERO system saves 34 million gallons per year.

	 •	 By recycling spent rinse water from the microelectronics’ processes for retreatment in the HERO 

system, Sandia saves 6 million gallons per year.

	 •	 By replacing potable water with reclaimed water from

the microelectronics’ processes for acid waste scrubbers 

and cooling towers, Sandia saves 40 million gallons 

per year.

Efficiency improvements in the production of high-purity 

water and the reuse of spent rinsewaters through recycling 

and reclamation has saved 80 million gallons of water per 

year, which represents about 18% of the total water use 

at Sandia. The estimated value in water and sewer costs is 

$160,000 annually. 

For More Information

FEMP Water Efficiency: http://www.eere.energy.gov/femp/

program/waterefficiency.html

Water Efficiency Best Management Practices: http://www.

eere.energy.gov/femp/program/waterefficiency_bmp.html

Sandia Water Efficiency: http://www.sandia.gov/aqua/

default.htm This simplified flow chart shows the general path of the 

recycled and reclaimed water in the MESA plant.

Water Recycling and Reclamation at the 

MESA Plant, Sandia National Laboratories