The 21st century is times of hydrogen. Because, it’s secondary energy same as electricity, hydrogen can be produced from various energy source. In short, fossil fuel as natural gas, coal and oil becomes raw materials of hydrogen, contrary, in long, renewable energy as solar power, wind and biomass should be use for produce hydrogen. This feature articles take up an energy source to produce hydrogen with a low cost. Especially, oil with energy saving, coal with CCT and biomass with biological methods.

Development of reforming catalysts (steam reforming catalyst, CO shift catalyst and CO removal catalyst (preferential oxidation)) has been carried out in order to achieve dramatic cost reduction for the reformer of PEFC systems in NEDO Industry-Academia Consortium Project. High durability under frequent starts and stops condition is required for the catalysts. A target catalyst for each cost is lower than 1OOOOyen/kW. Base metal catalysts which enable to reduce a cost and high durability were found out. Manufacturing process for the catalysts was also developed. Development of new CO selective methanation technology was also carried out for further cost reduction.

There are two main processes to make hydrogen from coal industrially. One is gasification process and another is dry-distilling process. The coal gasification furnace and the coke oven are known as equipments for gasified and dry-distilled coal, and those technologies are used for generating hydrogen widely now.

This report describes about the features and trends of more suitable gasification furnaces for generating hydrogen in the world and three attractive hydrogen manufacturing technologies, the HYCOL process, the HyPr-RING process and non-catalytic Hot COG reforming process.

The HYCOL gasification technology was promoted as the first technical development for hydrogen from coal by Japanese government. The HyPr-RING process is attractive attention from all over the world as new development technology of manufacturing hydrogen from coal and in-situ CO₂ capture. And, the non-catalytic Hot COG reforming process is the state-of-the-art technology for hot coke oven gas (hot COG) reforming.

We carried out pilot demonstration tests of hydrogen fermentation with biomass as the initial step to start a commercial. Specifically, we attempted to obtain the optimum conditions to hydrolyze non digestible food wastes and bagasse, which is the squeezed residue of sugarcane, and to operate the hydrogen fermentation process by applying the ‘Two-stage hydrogen and methane fermentation’. The two-stage hydrogen and methane fermentation exceeded the methane single fermentation in terms of energy balance. The obtained ‘BioHydrogen’ consists of 60% hydrogen and 40% carbon dioxide. Additionally, no sulfide was detected This BioHydrogen, therefore, can be used in a Fuel Cell without desulfuration. We achieved 2.4 kmol-H₂/kmol-consituent sugar, and 80% rate of gasification from the food waste and 2.4 kmol-H₂/kmol-consituent sugar, and 91% rate of gasification from bagasse.

Economical analysis on fermentative hydrogen production from cultivated seaweeds was studied. Productivities of seaweeds were approximately 145 ton/ha at Laminaria japonica ARESCH, 150 ton/ha at Sargassum horneri, 105 ton/ha at L. japonica, etc. by 4months cultivation. From 1 ton-wet of L. japonica ARESCH, ca. 80 kg of mannitol and 16 Nm³-H₂were expected to obtain. By selling 48 ¥/kWh, which is the legislated price for solar sell power, the income from surplus power was 1,214 ¥/ton after necessary use for fermentation. If it is possible to produce hydrogen by the theoretically maximum yield from mannitol, the income increases to 3,945 ¥/ton. This means that the production of hydrogen from seaweed by fermentation will be payable by reducing the production cost of seaweeds below 1,500 ¥/ton. It was proposed to find new bacteria which have higher property on hydrogen yield than a bacterium found at Tanisho’s lab which is able to produce hydrogen at a small yield from alginate to make economics sure.

We have a large amount of geothermal resources (23470MWe) in Japan but only a few percent (535MWe) of the resources have been developed. It is very important to utilize geothermal energy with other renewable energies in order to realize energy security and low carbon society. The first problem to be solved in increasing geothermal energy utilization is cost performance. FIT (Feed In Tariff) system will improve the situation dramatically. The second problem is environmentally adaptable development in the national parks where more than 80% of promising geothermal resources are stored and the third one is to develop geothermal energy in cooperating with utilization of hot springs. Geothermal energy will contribute much more to energy demand in Japan by solving the above problems.