Osaka Gas Co., Ltd. (President: Hiroshi Ozaki; herein “Osaka Gas”), Aisin Seiki Co., Ltd. (President: Fumio Fujimori; herein “Aisin”), Kyocera Corporation (President: Tetsuo Kuba; herein “Kyocera”), Chofu Seisakusho Co., Ltd. (President: Yasuo Kawakami; herein “Chofu”) and Toyota Motor Corporation (President: Akio Toyoda; herein “Toyota”) announced that they have completed co-development of a residential-use solid oxide fuel cell (SOFC) co-generation system (herein “SOFC system”)*1.
The new product — “ENE-FARM Type S” — derived from the companies co-development project achieves a power generation efficiency of 46.5%*2, the highest level in the world*3 for a residential-use fuel cell. Within the co-development agreement, Kyocera produces the cell stack*4; Aisin the generation units with the cell stack incorporated into it; Chofu the hot-water supply and heating unit using exhausted heat; and Osaka Gas will commence sales of the system on April 27, 2012 (only available to the Japanese market) at the standard price of ¥2,751,000 (tax included). The companies will successively expand their production operations and will strive to promote the widespread use of this SOFC system.
The SOFC system has been developed based upon the companies’ advanced technology in areas such as the design, installation and maintenance technology of Osaka Gas for co-generation systems; the design and production technology of Kyocera for cell stacks; the design and production technology of Aisin/Toyota for generation units; and the design and production technology of Chofu for hot-water supply and heating units using exhausted heat. The companies submitted 121 units in total to the “Demonstrative Research on Solid Oxide Fuel Cell” project undertaken by the New Energy and Industrial Technology Development Organization (NEDO) and the New Energy Foundation.
ENE-FARM Type S utilizes ceramic electrolyte for the power generating cell stack which achieves a high operating temperature of 700 to 750 degrees Celsius. This high temperature heat can be efficiently used as energy to reform utility gas to hydrogen and thus a high power generation efficiency level of 46.5% is achieved — with an overall energy efficiency of 90.0%*2.
The SOFC system includes a hot-water supply and heating unit which uses exhausted heat with a storage tank at a small size of 90 liters to optimally utilize the high temperature heat exhausted during power generation; as well as a high efficiency latent heat recovery type hot-water supply heating unit for the back-up boiler.
Through these measures, the system is environmentally and economically enhanced, and eliminates annual CO2 emissions of about 1.9 tons while also reducing annual energy costs of about ¥76,000 compared to ordinary gas-powered hot-water supply and heating units*5.
Moreover, due to the low number of parts and small quantity of exhaust energy, a compact design was made possible for both the power generation unit and the hot-water supply and heating unit — thus allowing it to be installed even at homes with limited installation space. In the future, the companies also plan to expand use of the system to apartment buildings.
ENE-FARM Type S Structure
Cell stack: Generates power through chemical reaction between hydrogen reformed from utility gas and oxygen in the air. Module: Contains the fuel reformer and the cell stack, and is covered with a thermal insulator to maintain a high temperature. Desulfurizer: Removes sulfur compound of odorant in the utility gas to prevent the cell stack and other parts from deterioration. Inverter: Converts DC generated by the cell stack into AC. Hot-water storage tank: Stores heat exhausted from the power generator as hot-water. Back-up boiler: Used for supplying hot-water and heating in case the hot-water storage tank is empty.
Features and Specifications Main features
(1) Achieved the highest level of power generation efficiency in the world at 46.5% The operating temperature of the electrolyte of the power generating cell stack is high at 700 to 750 degree Celsius, therefore, this heat energy can be effectively utilized as the energy necessary to reform utility gas to hydrogen. Through improving thermal insulation properties of the module comprised of the cell stack and others, the companies could increase the heat energy utilized. Because of this improvement, the companies achieved the highest level power generation efficiency in the world at 46.5%. (2) Roughly 80% of household power consumption can be supplied Most of the household power consumption can be supplied by in-house power generation through operating the new product continuously as needed. (3) Standard inclusion of high efficiency back-up boiler Hot-water prepared with exhausted heat during power generation is used in the bathroom, kitchen and other places. If the hot-water storage tank is empty, the built-in back-up boiler will supply hot-water. The boiler is a high efficiency latent heat recovery type for reusing burned gas. (4) Compact A compact hot-water storage tank of 90 liters to store exhausted heat is installed Designing a thin stainless steel tank, the depth has been decreased down to 310mm of the hot-water supply and heating unit using exhausted heat. Required installation space was decreased to approximately 1.9m2 consequently (minimum installation space is approximately 1.6m2 with optional side exhaust gas cover).