SOEST Open House

HNEI Researchers Participate in 2019 SOEST Open House

HNEI is an organized research unit under UH Manoa’s School of Ocean and Earth Science and Technology (SOEST). The School holds an Open House biennially that showcases activities and demonstrations highlighting research conducted by its various departments.

The 2019 SOEST Open House featured presentations of current research In HNEI's grid integration and battery technology research areas, led by Leon Roose and Matthieu Dubarry respectively.  Partnering with ENGIE, HNEI’s GridSTART group members, Kevin Davies and Saeed Sepasi produced an exhibit that featured hands-on activities to demonstrate integration of renewable energy, power generation, and energy efficiency.  George Baure, Jr. also presented how electrochemical power systems work using battery technology.


2019 OH1

2019 OH2


HiSERF Proton Electrolyzer

HiSERF Proton Electrolyzer Exceeds Manufacturer Stack Lifetime Estimates by Over 60%

According to Keith Bethune, an Assistant Specialist at HNEI's Hawaii Sustainable Energy Research Facility (HiSERF) fuel cell laboratory, an on-site electrolyzer reached 12.3 years of production, exceeding the expected lifetime of the three original stacks by over 60%.  The Proton On-Site H-Series Electrolyzer installed in October 2006, achieved 107,100 hrs of production on the three original electrolyzer stacks. This far exceeded the manufacturer’s expected lifetime of 60,000 hrs for the 2005 stack design. The unit has a maximum production rate of  6Nm3/H (107.6 SLPM) and during operation approximately 3,400 kg of hydrogen were produced supporting fuel cell testing operations at the facility. The overall system, including the Proton electrolyzer, cooling water chiller, and deionized water supply unit had a 99% uptime over the life of the electrolyzer stacks. The majority of the shutdowns were due to peripheral equipment issues, routine maintenance, power outages, and a planned 6 month shutdown of the lab.   

The three electrolyzer stacks were replaced in one day and the unit was restarted in mid-August. The ease of stack replacement further contributes to the availability of the equipment and the stack longevity has been attributed to a strict adherence to maintenance scheduling for all components in the system, particularly the quality of the feedwater into the system.  

With proper maintenance and maintaining quality inputs into the system (feedwater), electrolyzers are a very reliable source of hydrogen and may even outlast the manufacturer specs.


HNEI to Analyze Life Cycle Greenhouse Gas Emissions of Energy Projects for PUC

In response to a request from the Hawaii Public Utilities Commission, HNEI is initiating a study to provide a quantitative assessment of GHG emissions for various energy products and production technologies used or expected to be used in Hawaii.  The outcomes from this study are intended to support the Commission's decision making.  HNEI will engage local and national experts on the topic and collaborate with local stakeholders on the the study's scope and results.  Further details regarding this collaboration can be found in the PUC letter.

Point of Contact: John Cole

ChemPhysChem Cover

HNEI Research Featured on ChemPhysChem Cover

HNEI Assistant Researcher, Dr. Godwin Severa, is featured on the ChemPhysChem journal cover for his publication "Kinetic Enhancement of Direct Hydrogenation of MgB2 to Mg(BH4)2 upon Mechanical Milling with THF, MgH2, and/or Mg".  This research was funded by the Department of Energy and conducted in collaboration with Department of Chemistry and the HYMARC Consortium.  The paper was designated as a Very Important Paper and is included in the journal's October 2019 issue ( 

Hydrogen storage remains one of the great challenges limiting the widespread availability of hydrogen PEM fuel cell technology for automobile and unmanned vehicles.  The magnesium boride, MgB2 to magnesium borohydride, Mg(BH4)2 system is one of the few reversible materials with potential to meet all the fuel cell vehicle requirements but is limited by poor kinetics of hydrogen release at optimum conditions.

This study improved upon the hydrogenation conditions of MgB2 to Mg(BH4)2  through modification of the MgB2, by mechanical milling with additives, resulting in a 300 bar and 100°C reduction in hydrogenation conditions compared to previous state of art while still achieving ~54–71% conversion to the borohydride. The discovery of such a form of modified magnesium boride presents an important step towards development of a practical hydrogen storage system.

Additionally, this paper was featured on the ChemistryView website at


HNEI Demonstrates Low-Cost Grid Monitoring and Controls Platform

HNEI recently demonstrated its Advanced Real-time Grid Energy Monitor System (ARGEMS) for the Alaska Center for Energy and Power, Alaska Village Electric Cooperative, and Arizona State University.  The system has reached a level of development where it is now being shared with external organizations.  Previous deployments have been in one of the Project Frog buildings on the University of Hawaii campus and as a part of HNEI’s conservation voltage reduction project in Okinawa Japan. 

HNEI Assistant Researcher, Kevin Davies, presented and demonstrated ARGEMS to the Alaska Center for Energy and Power on July 17 (see ACEP announcement) and the Alaska Village Electric Cooperative on July 22. The main objective of these ongoing discussions is to explore how the system could be used to monitor the performance of electric grids in remote Alaskan villages.  In June, HNEI delivered its second unit to Arizona State University under the Distributed Electrical Architectures from Circuits to Systems project funded by the Office of Naval Research’s Defense University Research-to-Adoption program. HNEI and ASU have begun to use ARGEMS to demonstrate distributed voltage control using power electronic inverters such as those for rooftop photovoltaics.

More information can be found at the ARGEMS project page and Alaska Center for Energy and Power's press release.

DOE Grant Awarded

HNEI Awarded US Department of Energy Contract

HNEI Assistant Researcher, Dr. Tatyana Reshetenko, has been awarded a 2-year contract from Pajarito Powder to characterize the performance and durability of a new generation of platinum-group metal (PGM) – free catalysts for fuel cells.  This effort is part of larger project “Active and Durable PGM-Free Cathodic Electrocatalysts for Fuel Cell Application” awarded to Pajarito Powder, HNEI, and IRD Fuel Cell by the US Department of Energy supporting early-stage research and development of innovative hydrogen and fuel cell technologies. The testing will be conducted at HNEI’s Hawaii Sustainable Energy Research Facility.

US DOE Press Release:

Early stage conceptual design for Sai Gon Energy Park

HNEI Supports Solar Energy Park Demonstration Project in Vietnam

HNEI and the Center for Regional and Urban Studies (CRUS) in Ho Chi Minh City, Vietnam, signed an agreement in July 2019 to develop a public Solar Energy Park (SEP) in Ho Chi Minh City.  Under HNEI's Asia-Pacific Regional Energy System Assessment (APRESA) program, CRUS will partner with local architects, engineers, universities, developers and city administration to design and construct a visible, education-based public pavilion featuring a solar PV system and various electric technologies.  The SEP will include an education component to increase public awareness of solar and other energy efficient technologies.

More information on this project can be found at

Alt Jet Fuel Pathways

HNEI Researchers Coauthor Review of Bio-Based Alternative Jet Fuel Production Options

HNEI researchers and collaborators published an extensive review of potential agricultural and silvicultural resources for the production of alternative jet fuel in Hawaii and the tropics.  HNEI partnered with UH Departments of Tropical Plant and Soil Sciences and Natural Resources and Environmental Management and Washington State University Department of Biological Systems Engineering on the project.  The report also summarized available data for these biomass resources undergoing pretreatment and conversion in alternative jet fuel production pathways.

Report: "Review of Biomass Resources and Conversion Technologies for Alternative Jet Fuel Production in Hawai’i and Tropical Regions" & Supporting Information
More information on this project can be found at

Molokai Dynamic Load Bank

HNEI Installs Dynamic Load Bank on Moloka'i

The Grid System Technologies Advanced Research Team (GridSTART) of the Hawaii Natural Energy Institute (HNEI), University of Hawaii, in collaboration with Maui Electric Company (MECO) and with funding from the U.S. Office of Naval Research (ONR), has proposed and installed a practical, inexpensive and effective solution to address the integration of very high levels of rooftop PV and the occasional excess of intermittent solar energy produced in aggregate by the PV systems on the Island of Moloka‘i.  In addition to serving as a means to efficiently balance total system generation and demand during periods of excess solar energy production relative to island power demand, the asset also serves as a grid stabilizing “safety valve” to rapidly absorb excess energy during unplanned system disruptions, such as a sudden loss of generation on the grid. This unique solution features a 750 kW resistive dynamic load bank connected to the island’s electrical grid.  The load bank is operated both autonomously using advanced controls according to predefined conditions and manually at MECO operator discretion from the utility control room.  The addition of this load bank on the grid has allowed MECO to release a hold (in place since 2015) on the interconnection queue for rooftop PV, allowing the addition of approximately 725 kW of new rooftop systems.  The island of Moloka‘i, with a daytime system demand that can dip as low as 3.3 MW, already has approximately 2.3 MW of rooftop PV in operation. This load bank provides a reliable means to prevent baseload diesel generation on Moloka‘i from going below its minimum reliable operating level (risking unit trip and island-wide blackout) due to excess rooftop PV energy production on the island.  GridSTART is continuing its work with MECO to develop and test the capabilities of the load bank to provide additional benefits such as frequency regulation and down reserves in coordination with a 2 MW battery previously installed and under test in further HNEI-MECO collaboration on Moloka‘i.

More information regarding this project:
HNEI Press Release:
UH News Press Release:

Additional articles: The Molokai Dispatch, Utility Dive, Civil Beat

Anaerobic Digestion Reactors

HNEI Researchers Publish Method for Cross Comparative Analysis of Anaerobic Digesters

HNEI researchers have published a methodology for cross comparative analysis of anaerobic digesters.  In this novel contribution, criteria to evaluate performance of different reactor designs using a common basis for comparison were developed and applied to over 82 reactors of various designs.  Results revealed general trends and general principles to guide application.  These findings were published in "Cross Comparative Analysis of Liquid Phase Anaerobic Digestion" in the Journal of Water Process Engineering.

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