Japan has long focused on building heating and cooling plants for each region .

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Minato Mirai 21 Heating and Cooling Company (DHC Mirai 21 District Heating & Cooling - DHC) in Yokohama City, Japan plays a role of air conditioning for nearly all Minato Mirai buildings - the central district. mind of Yokohama - (Photo: VnEconomy).

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With close coverage of 186 hectares of Minato Mirai district, DHC guarantees "warm winter, cool summer" for 1,770 companies with 190,000 employees, and nearly 10,000 residents in the county - ( Photo: VnEconomy).

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DHC provides heating in winter and cooling in summer by bringing hot or cold water from the plant through the underground pipeline system to the inside of the walls of the buildings - (Photo: VnEconomy).

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Through unified management of heating and cooling instead of using the air conditioning system for each building, the "whole county" air conditioning model like DHC helps to use energy efficiently and limit environmental pollution, and avoid the risk of system disruption in case of natural disasters - (Photo: VnEconomy).

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For customers, using DHC's heating and cooling services means that they do not have to install their own bulky and expensive systems - a must for buildings in a country with an etched climate. Harsh like Japan.The liberated area can be used for other purposes such as office, parking . Besides, customers can save personnel costs for operating air conditioning systems - Photos : VnEconomy.

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In DHC's factory, attached to high-temperature steam generators and water cooling are giant pipes.These pipes will run through the ground of Minato Mirai district, besides drainage, electricity, disaster warning, monitoring, water, gas supply, dust collection, fiber optic Internet and television . - (Photo: VnEconomy).

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Founded in 1986, DHC currently provides heating and cooling for a total surface area of ​​nearly 3.2 million m 2 .However, the number of employees of the company only includes 82 people- (Photo: VnEconomy).

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Due to the use of modern equipment, DHC's factory has almost no workers shadow - (Photo: VnEconomy).

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DHC's annual revenue is about 7.9 billion yen, equivalent to about 71 million USD, profit ratio is about 5-6%.This is a private company, but received capital support from the Yokohama city government - (Photo: VnEconomy).

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To warm up, hot steam is transmitted from DHC plants with a steam transmission pressure of 0.78 MPa, and when returned it has a temperature of 60 degrees Celsius. For cooling, water is transmitted from the plant. has a temperature of 6 degrees Celsius, and returns at a temperature of 13 degrees Celsius - (Photo: VnEconomy).

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Compared to each building's own heating system, the general air conditioning service saves 10% energy.Particularly for DHC, energy saving efficiency reached 23% - (Photo: VnEconomy).

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There are 4 heating and cooling plants like DHC in Yokohama city, and there are about 140 similar facilities all over Japan - (Photo: VnEconomy).

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Central control room in DHC's factory - (Photo: VnEconomy).

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This company is considered as one of the typical factors for sustainable urban development model of Yokohama, the second largest city of Japan - (Photo: VnEconomy).