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Social Innovation

Energy-Efficient Air Conditioning to Keep Shinjuku Comfortable Energy-Efficient Air Conditioning to Keep Shinjuku Comfortable

  • Urban Development
  • Energy

A massive heating and cooling center becomes more efficient thanks to Hitachi Appliances' innovative new chiller.

Just west of the heart of Tokyo is Shinjuku, one of the busiest business districts in all of Japan. Amidst this bustling center of activity, a group of skyscrapers is connected by a single underground pipe - one that stretches for some 8 kilometers (about 5 miles)! This pipe leads to the Shinjuku District Heating and Cooling Center. One of the largest facilities of its kind in the world, this Center generates hot and cold water to supply heating and cooling to buildings in the area.

If each building in the area has its own heating and cooling system consisting of a heat source, boiler, and chiller, the level of air pollution becomes a major concern. That's why this Center was opened in 1971 to centrally manage air conditioning in groups of buildings throughout the region with an energy-efficient heating and cooling system.

Isamu Iida, Deputy Director, Shinjuku District
Heating and Cooling Center

At the core of this amazing Center are the centrifugal chillers developed and manufactured by Hitachi. Its wide variety of products includes chillers capable of generating up to 10,000 refrigeration tons(RT)*, the equivalent of 14,000 air conditioners for 13m2 rooms. They also play a key role in reducing the Center's overall environmental impact. Through several replacements over the years, these chillers have ensured a comfortable atmosphere in the buildings that keep Japan's economy moving.
The latest replacement project was launched in 2011. With sights set on providing even better environmental efficiency, a numerical target was set: "0.9". What does this number mean? Read on to find out.

One refrigeration ton is the heat required to convert one ton of 0 degree Celsius water to one ton of ice in 24 hours. Calculated as 10,000 refrigeration tons=35,163kW and the capacity of a room air conditioner for a 13m² room is 2.5kW.

Project Summary

Challenge: Design a more efficient chiller to meet the Center's target COP of 0.9
The massive Shinjuku District Heating and Cooling Center supplies air conditioning to buildings in the busy Shinjuku district of Tokyo. Its operators wanted to upgrade it to a more eco-friendly system with a target COP of 0.9, so Hitachi set out to develop its most energy-efficient chiller ever.

Solution: Switch from steam power to electricity and rearrange the layout
Two Hitachi engineers, one a seasoned veteran who had worked on the last "legendary" chiller, came up with a plan to change from steam to electric power. They also rearranged the layout and split the work into two main units. This design made the chiller more efficient and easier to use.

Result: A chiller is delivered that starts more quickly and runs more efficiently
Not only did Hitachi help the customer meet its target, they also delivered a chiller that truly impressed everyone with its start-up speed and efficiency of operation. With maintenance and technological cooperation, the team hopes to keep it running and maintaining its efficiency for 35 years.

The information in this contents is current as of December 2013.

Energy Advance Co., Ltd.

District Cooling Systems


Release Date:
Dec. 2014

Products & Services:
Air Conditioning

Solutions By:
Hitachi Appliances, Inc.