TOKUMARUTTO Complex Introduces High-Efficiency Geothermal Air Conditioning and Hot Water System

Eizen Corporation, a subsidiary contractor of Innovex engaged in high-efficiency geothermal air conditioning systems, announced that it has installed the geothermal air conditioning system “Surches®” at TOKUMARUTTO, a mixed-use facility opened in February 2026 by Tokushima Kogyo Co., Ltd. The system covers floors 1 through 4 of the building, which spans from one basement level to four above-ground floors, and a group home has opened on those floors. This marks the first installation of Surches® in a commercial facility. Tokushima Kogyo is a real estate development company that mainly owns and manages properties in Tokyo’s Itabashi area. When building the new TOKUMARUTTO complex, the company decided to introduce the environmentally friendly Surches® energy air conditioning system, which uses geothermal heat, to help address local community issues while reducing environmental impact. Group homes need to maintain comfortable room temperatures 24 hours a day, 365 days a year, which leads to high electricity consumption from air conditioning. Rising fuel costs have therefore become a major management issue. By using geothermal and groundwater heat, which remain stable at 15 to 18 degrees Celsius throughout the year, Surches® enables a next-generation facility management model that addresses these operating challenges. The system was chosen for three main reasons. First, it can be installed in a compact space equivalent to two parking spots. Heat Cluster®, a patented technology, delivers about five times the heat exchange performance of conventional geothermal methods. By using both groundwater and geothermal heat, it significantly improves heat collection capacity and enables efficient heat use with fewer heat source boreholes. In this facility, only three boreholes were required, compared with 12 to 15 under other geothermal methods. Second, the system enables temperature control by floor. While large facilities such as factories often use large air handling units to condition an entire building, TOKUMARUTTO uses ceiling-embedded fan coil units on each floor. This allows each floor to be temperature-controlled according to conditions in each area, maintaining comfort while further improving energy efficiency. Third, Surches® substantially reduces running costs and CO₂ emissions. For this facility, annual operating costs are estimated to decrease by about 2.44 million yen, while annual CO₂ emissions are estimated to fall by about 47.7 tons. Both figures are estimates. By using a Tokyo Metropolitan Government renewable energy subsidy program, the additional upfront cost compared with ordinary air conditioning equipment is expected to be recovered in four years. Eizen Corporation said it will continue contributing to an environmentally conscious society through installations of the Surches® geothermal air conditioning system, backed by more than 40 years of trust in its existing businesses and proven technical capabilities demonstrated in public works projects. Founded in 1976 in Maebashi, Gunma Prefecture, near the southern foot of Mount Akagi, Eizen Corporation has spent nearly half a century handling public and private construction projects that support regional infrastructure. Since 2022, it has also been developing geothermal air conditioning construction as a third core business in the renewable energy field. The company’s geothermal systems use proprietary technology from Innovex, combined with Eizen’s accumulated construction know-how. Eizen says it aims to contribute to a sustainable society for future generations while pursuing its corporate mission of creating comfortable environments for people.