CO2 defrost system cuts energy use by 20% for Japanese distributor Kyodo Suisan Ryutsu
July 21, 2023
In 2021 Japanese food and beverage distributor Kyodo Suisan Ryutsu replaced its aging R22 refrigeration system with transcritical CO2 (R744) condensing units at its cold chain distribution center adjacent to the Tokyo metropolitan area.
Notably, the new defrosting system, which employs off-cycle, heater and warm brine defrost, has achieved an “average energy savings of 20% compared to [that of] the R22 refrigerator,” said Takashi Kaneko, President and Representative Director of Kyodo Suisan Ryutsu.
In 2019, operators at the distribution center – which opened in 1988 – started looking to transition to natural refrigeration due to growing troubles with its R22 system, said Kaneko. The company replaced all of its R22 units with six Super Green CO2 condensing units manufactured by Japanese-based Nihon Netsugen Systems.
Of the six units installed, two operate in a low-temperature (Class F) mode, both with a cooling capacity of 101.7kW (28.9TR) at -25°C (-13°F); three units operate in medium-temperature (Class C) mode, each with a cooling capacity of 38.2kW (10.9TR) at 10°C (50°F); and one unit runs in dual-purpose mode for both Class F and C operation.
The company is considering replacing its R32 air-conditioning system in the distribution center with a CO2 one, he added.
Nihon Netsugen meets growing CO2 demand
Headquartered in Tokyo, Nihon Netsugen launched its first Super Green CO2 condensing unit on the Japanese market in 2015 “with the aim of obtaining stable operation in hot summer climates and provid[ing] energy savings on an annual basis,” said Nihon Netsugen.
The Super Green offers temperature ranges from -43 to 10°C (-45.4 to 50°F) and is capable of reducing energy consumption by 20–30% compared to R22 systems, the manufacturer said. Nihon Netsugen had sold 345 of the units in Japan as of February 2022.
The manufacturer opened a new manufacturing facility in Shiga, Japan, last March to meet the growing demand for transcritical CO2 refrigeration systems in the region, according to Katsuhiko Harada, President of Nihon Netsugen. The new facility will boost the manufacturer’s production ability from 100 units annually to 250.
“We were expecting many Japanese customers to choose HFOs over natural refrigerants as a freon-heavy market,” Harada said. “But that’s not the case; they’re really interested in natural refrigerants.”
Established in 1987, Nihon Netsugen has partnered with various European manufacturers to bring natural refrigerant products to the Japanese market. Besides the CO2 condensing unit, the company also offers a CO2 brine chiller, air-source, water-source and geothermal heat pumps, ammonia (R717) refrigeration units and other sustainable systems for large commercial and industrial applications, according to the company’s website.