National Institute of Advanced Industrial Science and Technology (AIST)

産総研トップへ

Hydrogen Energy Carrier Team

Production and Utilization Technology of Hydrogen Energy Carrier

Over View

 Renewable energy such as sunlight and wind power is clean natual resource which is significantly valuable for Japan due to that most of energy resource consumed in Japan is imported from foreign countries. However, since renewable energy is unstable and/or quite dependent on weather and place, amount of electric power acquired with renewable energy is also unstable. Production technologies of hydrogen energy carrier are water electrolyzation technology to produce hydrogen with such unstable electric power, and chemical energy conversion technology of electrolyzed hydrogen with catalyst. These technologies are necessary to introduce a large amount of renewable energy.

Research Target

 The team has great challenges to solve energy issues by developing technologies of energy storage and utilization for a massive penetration of renewable energy in the future.
 We have been developing technologies on energy conversion of renewable electricity into hydrogen or hydrogen energy carrier which is utilized by generating electricity and heat or is utilized as a fuel for vehicles. These technologies are quite useful to stabilize storage and to supply renewable electricity generated by using renewable energy which is susceptible to change of weather. It will be consequently achieved that much more renewable energy can be used efficiently regardless of locations and seasons, and can solve energy security issues in the future.

Research Outline

 The team has been developing a set of hydrogen technologies using electric power generated by fiuctuating renewable energy: hydrogen production of water electrolysis, chemical conversion into hydrogen energy carrier, and utilization of hydrogen. The basic technologies such as production of hydrogen energy carrier and catalysts for that, and hydrogen engines are applied to large scale demonstration equipment, and the knowledge gained through the experiments will achieve a technical breakthrough:

  • Technologies for high-efficient production of hydrogen energy carriers (e.g. organic chemical hydride, ammonia,formic acid). We are developing high-efficient technologies for the catalyst synthesis.
    ※Methylcyclohexane (MCH): Organic compound containing 6 wt% hydrogen, which is liquid at room temperature and atmospheric pressure. One L of MCH stores 500 L of hydrogen gas.
    ※Formic Acid: Organic compound containing 4wt% hydrogen, which is liquid at room temperature and atomospheric pressure. Formic acid is produced by synthesising carbon dioxide and hydrogen. One L of formic acid stores 600 L of hydrogen gas.
  • Technologies on combustion use of hydrogen or hydrogen energy carriers for co-generation engines and gas turbines.
  • Demonstration of an integrated system of hydrogen production/utilization. A new system to optimize storage and utilization of electric power generated by renewable energy will be proposed through this experiments.

Energy network including hydrogen energy carrier

Main Research Facilities

Hydrogenation/Dehydrogenation Reaction Apparatus Advanced Co-generation Engine
Hydrogenation/Dehydrogenation Reaction Apparatus Advanced Co-generation Engine
Catalytic hydrogenation and dehydrogenation reaction are analyzed by on-line gas chromatography. Fluctuating hydrogen simulating derived from renewable energy also can be supplied. Excessive operational experiment and multi-fuel engine combustion technology with hydrogen, diesel fuel, etc by use of 4 cylinder diesel engine (Displacement:5.2L)
Hydrogen Energy Carrier Production/Utilization System
Image:Hydrogen Energy Carrier Production/Utilization System

The world largest class MCH production and utilization demonstration.
This demonstration system integrates large scale alkaline water electrolyzer, catalytic hydrogenation reactor, large storage tanks, and co-generation engine with catalytic dehydrogenation reactor.

[Specification]
Hydrogen generation capability by alkaline water electrolysis: 34 Nm3/h
Hydrogenation to toluene: 70 L/h (MCH production capability)
MCH storage capacity: 20 kL (conversion into power generation: about 10 MWh)
Co-generation 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】

 Over a hundred kinds of products and their concentration have been analyzed quantitatively by using a catalyst evaluation apparatus with an on-line GC. Developing a design guideline of a production process of organic chemical hydride and collecting data for standardization in the future market. At the moment, analyzing behaviors of products and by-products formation by circulating processes of hydrogenation and dehydrogenation.

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

 The world largest class hydrogen energy carrier production and utilization system was launched. This system integrates large scale alkaline water electrolyzer, catalytic hydrogenation reactor, large storage tanks, and co-generation engine with catalytic dehydrogenation reactor. 10 MWh of electricity (Equivalent to 1000 days of ordinary home electricity consumption) has been stored by hydrogen or MCH in the last one year. This system will be combined into the energy network in FREA to suggest a strategy for electricity storage and utilization.


3. Advanced Co-generation Engine by use of H2 from MCH 【Fig. 2】

 The team is conducting research and development for the next-generation cogeneration engine with a dehydrogenation catalytic reactor of MCH which can recover engine exhaust heat. Also a dual fuel engine combustion technology of diesel and reformed hydrogen from MCH is being developed. The world’s best hydrogen generation from MCH is realized by enhancing the recovery of heat such as the elevated temperature of engine exhaust heat. In terms of an engine combustion technology with hydrogen, 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.


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 an internal combustion engine firing ammonia 【Fig. 3】
 

 For combustion use of ammonia, micro gas turbine (rated power:50kW) combustion has been challenged, and 41.8kW power generation was successfully achieved by burning methane-ammonia gas or 100% ammonia. These are world's first research results.
 This research and development is conducted under the Crossministerial 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