Hydrogen Infrastructure Testing and Research Facility Animation

The Hydrogen Infrastructure Testing and Research Facility (HITRF) integrates hydrogen production, compression, storage, and dispensing into a unified system for fueling fuel cell electric vehicles and tracking hydrogen infrastructure performance. This animation shows how hydrogen flows through the integrated HITRF components.

Text Version

Green dots represent electricity, blue dots represent low-pressure hydrogen, and red dots represent high-pressure hydrogen.

Learn more about HITRF capabilities and projects in these areas.


NREL's electrolyzer stack test bed in the Energy Systems Integration Facility is a flexible platform for large active area stack testing with AC-DC power supplies capable of 4,000 ADC and 250 VDC. Stack and individual cell voltage measurements are taken to provide real time monitoring of stack and cell efficiency. The electrolyzer system provides house hydrogen to NREL's research projects and hydrogen fueling station.


Hydrogen Storage Systems

  • Low-pressure hydrogen storage: eleven steel hydrogen tanks at a pressure up to 200 bar (20 MPa) that can store 190 kilograms of hydrogen at full pressure. This system provides house hydrogen to fuel cell labs and feeds compressors capable of pumping to 415–900 bar (41.5–90 MPa).
  • Medium-pressure hydrogen storage: six hydrogen tanks at a pressure up to 415 bar (41.5 MPa) that can store 85 kilograms of hydrogen at full pressure. This system provides hydrogen to fill fuel cell forklifts and feeds the high-pressure compressors.
  • High-pressure hydrogen storage: six Type II hydrogen tanks at a pressure up to 900 bar (90 MPa) that can store 90 kilograms of hydrogen at full pressure. This system provides hydrogen to high-pressure research projects and for fuel cell electric vehicle fills.


  • The low-pressure to medium-pressure compressor can take hydrogen from 7 bar up to 415 bar (0.7 MPa to 41.5 MPa). It is an outdoor-rated, 50 kg/day diaphragm compressor with two stages of compression.
  • The medium-pressure to high-pressure compressor can take hydrogen from 415 bar up to 900 bar (41.5 MPa to 90 MPa). It is an outdoor-rated, 480 kg/day linear piston hydraulic compressor.
  • The low-pressure to high-pressure compressor can take hydrogen from 20 bar up to 478 bar (2 MPa to 47.8 MPa) in the first stage and from 478 bar up to 930 bar (47.8 MPa to 93 MPa) in the second stage. It is an outdoor-rated, 60 kg/h diaphragm compressor.

NREL collects data on compressor maintenance and reliability, process gas quality, and power and energy demand.


Chiller and Heat Exchanger

A 9-horsepower chiller supports H70 (70 MPa/700 bar) hydrogen refueling for fuel cell electric vehicles. The chiller and heat exchanger aim to pre-chill the hydrogen gas entering a fuel cell electric vehicle down to -40°C. NREL collects power data to measure chiller performance. On a warm day with the dispenser idle (no fills) the chiller uses 44 kWh of electricity per day. The chiller uses 4 kWh of energy to recover from a fill.


The H70 (70 MPa/700 bar) hydrogen dispenser is capable of fueling hydrogen fuel cell vehicles to SAE J2601 and MC Formula standards. The dispenser also has an H35 (35 MPa/350 bar) line that can fill fuel cell forklifts and provide non-pre-chilled hydrogen fills to fuel cell electric vehicles. The fuel quality is checked periodically to ensure the station adheres to the SAE J2719: Hydrogen Fuel Quality for Fuel Cell Vehicles standard.

NREL has also developed a research dispenser for conducting experimental fills where parameters such as gas temperature, pressure ramp rate, and flow rate can be adjusted. This dispenser can recirculate high-pressure hydrogen back to low-pressure storage, which conserves hydrogen gas and allows for accelerated testing. This capability has been used to perform accelerated testing and cycling of 700 bar hydrogen components including nozzles, receptacles, various service valves, and dispensing hoses to identify part failures that lead to low station reliability. A programmable test apparatus can cycle the equivalent of eight dispenser assemblies at once under representative pressure, temperature, and flow conditions typically seen during vehicle fueling.

Fuel Cell Electric Vehicles

Hydrogen fuel cell electric vehicles (FCEVs) are clean, efficient, refuel quickly, and provide long driving range. The challenges to widespread deployment include hydrogen infrastructure cost and reliability and fuel cell durability and reliability. NREL has two FCEVs on loan from partners in its fleet. These FCEVs allow NREL to educate visitors and the public about hydrogen and FCEVs as well as evaluate the hydrogen fueling experience and requirements.

Fuel Cells

The HITRF provides an integrated hydrogen distribution network to multiple fuel cell and hydrogen energy sciences laboratories within the Energy Systems Integration Facility.

Safety and Analysis

Data Analytics

NREL uses an automated data logging system to collect operating and maintenance data from all the HITRF components and report on every facet of hydrogen station performance. The National Fuel Cell Technology Evaluation Center (NFCTEC) at NREL regularly collects and compiles maintenance data from forecourt hydrogen stations. NREL is combining the data collected from the HITRF with NFCTEC data to improve the public knowledge of hydrogen station costs and operating requirements.


The HITRF is representative of current commercially available hydrogen fueling stations, as well as pre-commercial components and subsystems. This enables NREL to validate current industry standards and methods for hydrogen fueling, provide data and expertise to organizations that are developing model codes and standards, and test next-generation fuel cell and hydrogen components for operation, monitoring, and safety.


NREL uses data collected from HITRF components and systems to develop and validate reliability improvement strategies.


NREL is working with partners to add high-flow-rate and high-fill-amount (e.g., heavy-duty vehicle) fueling capabilities to the HITRF. Planned capabilities include additional high-pressure storage and a new dispenser.

Research Projects

The HITRF supports many different research projects at NREL. Example projects include:

  • Collecting data to track maintenance, reliability, and power and energy demand of major station components
  • Developing a device to test a hydrogen station's ability to perform back-to-back fills
  • Repeatedly cycling dispenser hoses under realistic conditions to identify common failure points and leak locations
  • Developing a gravimetric hydrogen standard for high-pressure hydrogen testing of commercially available flow meters
  • Verifying new hydrogen production, compression, and dispensing technologies in current fueling requirements
  • Benchmarking dispenser component failures to identify conditions at failure and predict dispenser component operation life
  • Modeling station requirements to complete high-flow-rate and high-fill-amount fueling.