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Advanced Energy

NREL and AE are teaming up on solar inverter testing.

Photo of a hybrid sport utility vehicle in motion; the vehicle is marked with the National Renewable Energy Laboratory logo.


NREL and Toyota are studying grid impacts of electric vehicles.

Photo of a glass cube containing power electronics equipment in a laboratory.


NREL and Wyle are building a hybrid power system for the Army.

The Energy Systems Integration Facility (ESIF) at the National Renewable Energy Laboratory (NREL) was recently designated a national user facility by the Energy Department, so utilities, industry, and other national laboratories can use the facility to develop their technologies with the added benefit of working hand-in-hand with some of the most expert grid integration scientists and engineers in the world. With the ESIF's megawatt-scale research, development, and testing capabilities, along with high performance petascale computing, there is no better place in the world to tackle today's grid integration challenges.

Become a Partner

User facility access to the ESIF is awarded through the review and approval of user proposals, depending on the scientific merit, suitability of the user facilities, and the appropriateness of the work to DOE objectives, and includes a signed user agreement for the facility. Learn more about partnering with NREL at the ESIF.

Current Partners

Industry, academia, and government are working together at the ESIF to modernize our electric infrastructure so it can accommodate the unique operating characteristics of renewable energy and energy efficiency technologies, modern building systems, and plug-in electric vehicles. The ESIF provides a way to test exciting new hardware and to make sure that it all works together in tomorrow's grid of the future.

Advanced Energy

Photo of a large gray inverter connected to numerous power cords.

500-kilowatt Advanced Energy inverter at the ESIF PSIL.
Photo by Dennis Schroeder, NREL

As the first industry partner to use the ESIF, Advanced Energy Industries is using the ESIF's Power Systems Integration Laboratory (PSIL) to test its new solar photovoltaic (PV) inverter technology with the facility's hardware-in-the-loop system and megawatt-scale grid simulators. Solar inverters are responsible for a number of critical functions within a solar PV system, including converting the direct current output into alternating current for the grid. Advanced Energy's inverter will help support a smarter grid that can handle two-way flows of power and communication while reducing hardware costs.

The hardware-in-the-loop system at the ESIF allows Advanced Energy to loop its inverter into a simulation environment so researchers can look at new technologies operating in a combination of real world, real power, and simulated or virtual environments to see the impact that these new systems are going to have on the reliability and quality of the power. The grid simulator can actually emulate a distribution circuit on an electric utility and simulate electric utility feeder response. The ultimate goal of the project is to increase PV saturation without negatively impacting the distribution grid through modifying the behaviors of inverters.

Watch a video on the Advanced Energy inverter testing at the PSIL.


NREL is quantifying energy savings from the Asetek rack under a real workload by comparing total power input to the system with total heat removed by liquid and air.
Photo by Dennis Schroeder, NREL 24699

To measure the energy savings, performance, and reliability of a warm-water direct-to-chip liquid-cooling retrofit solution for data centers, an Asetek RackCDU liquid-cooling system was installed as a retrofit to an existing air-cooled system in the ESIF high performance computing (HPC) data center.

The ESIF's state-of-the-art HPC data center is designed to be the most energy-efficient data center in the world, achieving an ultra-efficient annualized average PUE rating of 1.06 or better—making it the perfect place to demonstrate Asetek's energy-saving liquid-cooling technology.

The Asetek system will reduce the total energy costs at the ESIF data center by improving the efficiency of its computer racks—and more broadly, this project will benefit taxpayers by proving the performance and reliability of this new technology so that it can be more readily deployed at federal data centers.


NREL has joined forces with Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) to develop a plug-and-play technology that will result in newly connected solar generation being automatically "discovered" and configured by the main generation control system. NREL will perform a review of communications protocols to identify important protocols that the plug-and-play solar microgrid controller must be compatible with. CSIRO will also collaborate with multinational engineering firm ABB on the project.

NREL will perform prototype testing of the microgrid controller in the ESIF to test the hardware's ability to manage the output power of a diesel generator in the presence of a load bank and solar simulator. The effort ultimately aims to simplify the integration, accelerate the deployment, and lower the cost of solar energy in hybrid distributed generation applications using this new plug-and-play solar technology.


Solar inverter manufacturer Solectria is partnering with NREL to test its SGI-500 utility-scale photovoltaic (PV) inverter at the ESIF. The testing will focus on the inverter's response to frequency and voltage normal and abnormal conditions.

The ESIF's utility-scale power hardware-in-the-loop capability allows Solectria to loop its inverter into a real-world simulation environment so researchers can see the impact of the inverter's advanced features on power reliability and quality. This one-of-a-kind testing capability allows Solectria to test its inverter's controls and functionality at full power—and determine whether its integration changes the landscape of the grid.


One of Toyota's Highlander fuel cell hybrid vehicles on loan at NREL.
Photo by Dennis Schroeder, NREL 25255

At the ESIF, NREL is collaborating with Toyota Motor Engineering & Manufacturing to study the potential grid impacts of plug-in electric vehicles when a large number of charging vehicles share common—and potentially inadequate—residential electrical grid components. Toyota has relocated 20 Prius plug-in hybrid electric vehicles to the ESIF's Medium Voltage Outdoor Test Area (MVOTA), which provides easy interconnection and testing alternatives for grid integration hardware. The project will provide confirmation on the levels at which vehicle loads become significant to distribution grid power quality challenges and will lead to foundational strategies for monitoring and control throughout the grid.

Through another agreement with Toyota, NREL has received four Toyota fuel cell hybrid vehicles to enhance NREL's research and development related to hydrogen fueling, infrastructure, renewable hydrogen production, and vehicle performance. The vehicles, on loan to NREL, are fueled with renewable hydrogen made from wind and solar energy thanks to the wind-to-hydrogen project, which uses wind turbines and photovoltaic arrays to power electrolyzer stacks that split water into hydrogen and oxygen. Testing will be performed in the ESIF's Energy Systems Integration Laboratory (ESIL), which provides a flexible, renewable-ready platform for research, development, and testing of state-of-the-art hydrogen-based and other energy storage systems.


Photo of a glass cube containing power electronics equipment in a laboratory

Prototype CUBE system at the ESIF PSIL.
Photo by Dennis Schroeder, NREL

Under a research agreement with Wyle Labs, NREL is working with the U.S. Army to develop the Consolidated Utility Base Energy (CUBE) System—a solar, battery, and generator hybrid power system that provides electricity to forward operating bases. The Army's Rapid Equipping Force is funding NREL to complete a prototype CUBE system and validate its performance, reliability, and projected fuel savings through a fully integrated test at the ESIF.

The project aims to create a more resilient and reliable microgrid designed to protect against extended power outages caused by natural disasters, accidents, or attacks—and, ultimately, to enhance electric power surety for national security. Testing will be performed in the ESIF’s Power Systems Integration Laboratory (PSIL), which contains an environmental chamber that provides expanded testing capabilities. The military’s ground vehicles must be able to perform in diverse climates and at extreme temperatures, and the capability to test systems in these environments will ensure our soldiers can conduct their missions in environments around the world.