No. 117: Separating and collecting carbon dioxide from coal-fired thermal power by physical absorption (February 25, 2012)

Technology

J-Power is currently separating and collecting carbon dioxide by chemical absorption that uses amine solution for ion binding. Chemical absorption cannot be free from a certain limit because the amount of carbon dioxide increases with the absorbed amount. Physical absorption applies a high pressure to carbon dioxide and dissolves it in a special alcohol solution. That is, physical absorption is better than chemical absorption if the process grows higher in temperature and pressure. The company is constructing a test plant for physical absorption that is scheduled to be open shortly. Because the test plant is conducting tests of chemical absorption, it is the first test plant in the world that has test facilities both for chemical absorption and physical absorption. It plans to accumulate data and knowledge of physical absorption until 2013.

J-Power is working on the substantial experiments to generate electricity by driving a turbine using flammable gas collected from coal. At the same time, it is conducting experiments on the shift reaction of gases to separate carbon dioxide and hydrogen for effective collection of higly-pure carbon dioxide. Physical absorption will supposedly become widespread because increasing generation efficiency inevitably makes the process higher both in temperature and pressure. At the same time, physical absorption allows for desulfuration simultaneously because the degree of solubility of hydrogen sulfide is high in the alcohol solution.

No. 116: Growing industry-government collaboration for an energy saving society (February 24, 2012)

Business trend

Apartments featured by energy saving are selling well in the Tokyo metropolitan district. For example, an apartment complex that introduced an energy management system puts off lights in the common place automatically depending on the situation in summer, runs air-conditioners in the energy-saving mode, and has a large-scale photovoltaic generation on the roof. Each apartment is equipped with a terminal to know its power consumption. This apartment complex is part of the ongoing regional project under the initiative of Toshiba and Yokohama city to increase the efficiency of power consumption.

Saitama city is working with Honda to build an environment-conscious city. Honda will construct an experimental house before the front gate of Saitama University coming spring. In this experimental house, such Honda’s technology as photovoltaic generation, household gas generator, and collecting power form an EV in an emergency will be utilized fully. Tokyo metropolitan government and Mitsubishi Estate will start the experiment of smart grid and install smart meters in several buildings to monitor power consumption. Tokyo plans to ask real estate companies to introduce the model to be developed in the project in the future. In Chiba Prefecture, Tokyo University and Mitsui Fudosan are working together on a system to utilize photovoltaic generation, gas electric power generation, and bio generation using garbage. Power interchange between multiple facilities is also being planned.

The moves to create energy are also spreading. Tokyo will establish a fund of several tens of billion yen coming June to subsidize redevelopment companies that introduce the cogeneration system. Kanagawa Prefecture will build a large-scale photovoltaic generation plant to supply power to 518 households this fall.

According to a research firm, the infrastructure business to construct an energy saving society will grow 3.7 times over the level in 2010 to about 3,300 billion yen in 2020. With the background of this rapid growth, industry-government collaboration is expected become widespread.  

No. 115: Using carbon dioxide to grow vegetables in the plant factory (February 23, 2012)

Technology

Chiba University and Tokyo Gas are jointly working on the effective utilization of carbon dioxide. Hydrogen is the driving force of the fuel cell vehicle, and carbon dioxide is generated in the process to create hydrogen. Chiba University uses the generated carbon dioxide to grow vegetables in the plant factory it operates. The research team led by Associate Professor Toru Maruo tries to sweet vegetables, facilitate their growth, and increase their production by enhancing photosynthesis using carbon dioxide for the first time in the world. They liquefy carbon dioxide collected in the hydrogen station operated by Tokyo Gas and transport the liquefied carbon dioxide in cylinders to the plant factory. The research members supply 320 kg of carbon dioxide to tomatoes every month.

It is currently a widespread method to burn LPG and heating oil and send the generated carbon oxide into the greenhouse. Tokyo Gas buries the carbon dioxide in the ground. If the research members get successfully results, Tokyo Gas can reduce the disposal cost and Chiba University can reduce procurement cost. As proverb goes, it is like killing two birds with one stone. In the ongoing research, members try to increase the carbon dioxide concentration of the 1,000-square-meter greenhouse by 2.5 times to 1,000 ppm. The research is expected to increase tomato production by 20% and increase the sugar content by 0.5-1.0 degree. The cost to separate, collect, and transport carbon dioxide needs further study, according to the engineer of Tokyo Gas. The report of the joint research is scheduled to be published in March.