Hydrogen Energy Carrier Team

Production and Utilization Technology for Hydrogen Energy Carrier

Over View

Since renewable energy is unstable and/or highly dependent on the weather and location, the amount of electric power generated by renewable energy is also unstable. The production technologies for hydrogen energy carriers are water electrolysis technology for producing hydrogen using such unstable electric power, and chemical energy conversion technology for electrolyzed hydrogen using a catalyst. These technologies are necessary in order to introduce a large amount of renewable energy.

Research Target

The team has been developing technologies for storing and utilizing a large amount of renewable energy that will help solve several energy issues facing Japan.
We have been developing technologies for converting renewable electricity into hydrogen or hydrogen energy carriers, which is utilized by generating electricity, heat, and hydrogen. These technologies are useful for stabilizing the power grid even when massive amounts of renewable energy are introduced in the future. The result will be the efficient use of a much greater amount of renewable energy regardless of the location and season.

Research Outline

The team has been developing a set of hydrogen technologies using electric power generated by fluctuating renewable energy: hydrogen production by water electrolysis, chemical conversion to a hydrogen energy carrier, and utilization of hydrogen. Basic technologies such as production of hydrogen energy carriers and the catalysts, and hydrogen engines are applied to large-scale demonstration equipment, and the knowledge gained through the experiments will lead to technical breakthroughs:

  • Technologies for high-efficiency production of hydrogen energy carriers (e.g. organic chemical hydride, ammonia, formic acid). We are developing high-efficiency technologies for catalyst synthesis.
    *Methylcyclohexane (MCH): Organic compound containing 6wt% hydrogen, which is liquid at room temperature and atmospheric pressure. One liter of MCH can store 500 L of hydrogen gas.
    *Ammonia: Nitride containing 17wt% hydrogen, which is liquefied at room temperature and pressure of 0.86 MPa. One liter of liquid ammonia can store 1300 L of hydrogen gas.
    *Formic acid: Organic compound containing 4wt% hydrogen, which is liquid at room temperature and atmospheric pressure. Formic acid is produced by synthesizing carbon dioxide and hydrogen. One liter of formic acid can store 600 L of hydrogen gas.
  • Technologies on the combustion of hydrogen or hydrogen energy carriers for cogeneration engines and gas turbines.
  • Demonstration of an integrated system of hydrogen production/utilization A new system to optimize the storage and utilization of electric power generated by renewable energy will be proposed through this experiment.
Production and utilization of hydrogen from renewable energy

Production and utilization of hydrogen from renewable energy

Main Research Facilities

Hydrogenation/Dehydrogenation Reaction Apparatus Advanced Cogeneration Engine
Hydrogenation/Dehydrogenation Reaction Apparatus Advanced Cogeneration Engine
Catalytic hydrogenation and dehydrogenation reactions are analyzed by on-line gas chromatography.
Simulated fluctuating hydrogen derived from renewable energy can also be supplied.
Hydrogen flow rate: 10,000 mL/min, toluene and MCH flow rate: 10 g/min
Excessive operational experiment and multi-fuel engine combustion technology with hydrogen, diesel fuel, etc., using a 4-cylinder diesel engine (displacement: 5.2 L)
Hydrogen Energy Carrier Production/Utilization System
Hydrogen Energy Carrier Production/Utilization System<

One of the largest demonstration systems of MCH production and utilization technologies in the world. This system integrates the alkaline water electrolyzer, catalytic hydrogenation reactor, large storage tanks, and cogeneration engine with the catalytic dehydrogenation reactor.

Hydrogen generation capability by alkaline water electrolysis: 34 Nm3/h
Hydrogenation to toluene: 70 L/h (MCH production capacity)
MCH storage capacity: 20 kL (conversion to power generation: about 10 MWh)
Cogeneration output (electric power and heat): power 60 kW and heat 35 kW

Activities and Achievements

1. Evaluation of catalytic performance of organic chemical hydride【Fig. 1】

Products and by-products have been quantitatively measured by using a catalyst evaluation apparatus with an on-line GC. Currently developing a design guideline for the production process of organic chemical hydrides and collecting data for standardization in the future market. Recently obtained fundamental data for the dynamic optimization of hydrogenation and dehydrogenation processes.

【Fig. 1】Hydrogenation and dehydrogenation cycle of MCH

【Fig. 1】Hydrogenation and dehydrogenation cycle of MCH

2.Unified demonstration system of hydrogen energy carrier production/utilization

One of the world’s largest demonstration systems for hydrogen energy carrier production and utilization was launched. The alkaline water electrolyzer in this system successfully converted 30 MWh of electricity to hydrogen (equivalent to 3000 days of ordinary home electricity consumption), and a new simulator capable of predicting the performance of the electrolyzer has been constructed. In addition, this demonstration system has been incorporated into FREA’s energy network and we will propose a strategy for electricity storage and utilization.

3.Advanced cogeneration engine using H2 from MCH【Fig. 2】

Development is underway on a next-generation cogeneration engine with a dehydrogenation catalytic reactor of MCH that can recover the exhaust heat from engines. The world’s best hydrogen generation from MCH is realized by enhancing the recovery of heat such as the elevated temperature of engine exhaust. In terms of engine combustion technology for dual fuel (hydrogen and diesel), high thermal efficiency exceeding 40% and high exhaust temperature were achieved. While the exhaust temperature usually drops at high efficiency, the MCH could be decomposed by retaining the high exhaust temperature. In addition, efficient and clean combustion technologies are improved by maintaining a higher exhaust temperature for dehydrogenation of MCH.

【Fig. 2】Thermal efficiency and exhaust gas temperature as a function of the hydrogen ratio of the next-generation cogeneration engine

【Fig. 2】Thermal efficiency and exhaust gas temperature as a function of the hydrogen ratio of the next-generation cogeneration engine

4.Development of internal combustion engine firing ammonia【Fig. 3】

This team is collaborating with Tohoku University on technology research for the direct combustion of ammonia. Work has been done on a micro gas turbine (rated power: 50 kW), and 41.8 kW power generation was successfully achieved by burning methane-ammonia gas or 100% ammonia. These are world-leading research results. In terms of nitrogen oxide (NOx) emission, the gas turbine fueled with ammonia emits less than 25 ppm of NOx by using NOx removal equipment. This emission level meets the standard of the Ministry for the Environment of Japan.
*This research and development is being conducted under the Cross-Ministerial Strategic Innovation Promotion Program (SIP) “Energy Carrier” of the Cabinet Office (management corporation: JST).

【Fig. 3】 Ammonia gas turbine

【Fig. 3】Ammonia gas turbine

Team Member

Title Name
Leader Taku Tsujimura
Chief Senior Researcher Tetsuya Namba
Researcher Hirokazu Kojima
Researcher Yuichi Manaka
Researcher Ryousuke Atsumi
Researcher Javaid Rahat
Researcher Dimitriou Pavlos