How Japan keeps its cool when temps are high

The World
uchimizu event

Japan has endured record-breaking heat the last few summers, and to cool off, some people perform uchimizu, the tradition of spreading water on roads and in front of homes to cool the air. It’s been shown to lower the surface temperature a few degrees.

At a recent uchimizu event at the Higo-Hosokawa Garden, participants in lightweight kimonos used wooden ladles to spray water in long arcs that caught the late-afternoon light.

“It’s not like air-conditioning, but it’s a way to give us a nice feeling of cool during the summer heat.” 

Koji Yamano

“It’s not like air conditioning, but it’s a way to give us a nice feeling of cool during the summer heat,” said organizer Koji Yamano.

Related: How people are keeping cool amid record-breaking temperatures

uchimizu
Japan has endured record-breaking heat the last few summers and to cool off, some people perform uchimizu, the tradition of spreading water on roads and in front of homes to cool the air. Abby Leonard/The World

Most Japanese households do have air conditioning — about 90%, the same as the US — but it’s used slightly differently. The most popular model in Japan is a “mini split” system of separate, ceiling-mounted units that are individually controlled. Most people only cool rooms they’re using, said Takashi Abe from Daikin Industries, one of the country’s largest air-conditioner manufacturers. “Electricity is expensive here, so people like this separate-room system.”

“American people are very sensitive to the heat, so they really love to set lower temperatures.”

Takashi Abe

In the US, the majority of households have central air conditioning, which cools the whole house, but can be over 20% less efficient than the Japanese system. With a central system, cooled air has to travel through ducts and can’t be turned off in unoccupied rooms. Americans also keep their houses colder. “American people are very sensitive to the heat so they really love to set lower temperatures,” Abe said. 

Related: Japan’s next emperor is a modern, multilingual environmentalist

Energy Star, a joint program of the US Department of Energy and Environmental Protection Agency, recommends home air conditioning be set to 78 degrees. The Japanese government recommends 82 degrees to save energy and also because it’s thought to be unhealthy to move between temperature extremes, an idea that has roots in Chinese medicine.

For some Japanese, American air conditioning culture can be surprising. Goki Sakaguchi, who works for the Tokyo Stock Exchange, spent three years in New York and said he was freezing in his office there. “This is kind of embarrassing, but I actually had to wear blankets,” he said.

Related: South Korea’s ‘No Japan’ boycott is new. But the wounds are old.

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