Cooling Tea with Nature

Even as the summer sun outside pushes temperatures above 30°C, inside Li Yanzhong’s tea processing workshop in Tanyang Village, Fujian, the air hums with a steady, cool breeze, providing a suitable temperature for tea processing. Unlike the noisy electric air conditioners that once dominated the space, the cooling here comes from a quieter, more sustainable source: the Tanyang Stream, just a few meters away.

Tanyang Village, nestled in the hills of southeastern China, is the birthplace of Tanyang Gongfu Tea, a variety with a 170-year history and a global reputation. This tea was so renowned that letters addressed simply to “Tanyang, China” would reach their destination. At the 1915 Panama Pacific International Exposition, Tanyang Gongfu Tea won a gold medal, alongside another iconic Chinese product, Moutai liquor. 

The production of Tanyang Gongfu Tea is highly demanding, particularly when it comes to temperature control. The tea’s delicate fermentation process requires a precise and steady temperature range of 20-25°C. Any deviation outside this range can negatively impact the quality of the tea, making the production process especially challenging during the scorching summer months.

For years, Li’s 240-square-meter workshop relied on traditional air conditioners. “We used to run six 5-horsepower air conditioners non-stop during peak season. The cost is very high.” He recalls.

That changed in 2024 when a team from the Hydrogeological Bureau of China National Administration of Coal Geology approached the village with an idea: harnessing Tanyang Stream, whose waters stay within the range of 19-25°C year-round, to cool down tea factories.

Li’s workshop became the first tea business to trial the “green air conditioning system”. Eight sleek fans now hang from the ceiling, circulating cool air without the harsh blasts of traditional AC. 

“The technology may sound futuristic, but the concept is straightforward," explains Yang Kai, an engineer from the Hydrogeological Bureau’s Tanyang rural revitalization team.

Yang describes the river as a natural refrigerant. “In summer, the stream is 7–10°C cooler than the air. Our system extracts cold stream water to replace the fluorine-based refrigerant in the air conditioner.”

“We only use the coolness of the river, not the water itself,” Yang emphasizes. “The water goes back to the stream unchanged—no pollution, no harm to fish or plants. It’s 100% eco-friendly.”

As a result, “the temperature is more even now,” Li says, pointing to a digital thermometer reading 23°C. “And over seven months of use, we’ve saved more than 10,000 Kilowatt-hours of electricity—that’s 5,300 yuan.” 

According to Yang, compared with traditional air conditioning units, this innovative cooling system reduces electricity consumption by about 30 percent. 

The implementation of green air conditioning system in Tangyang Village has been spearheaded by the Tangyang Rural Revitalization Task Force of the Hydrogeological Bureau, as a proactive response to China’s rural revitalization policy.

The project represents a mutual choice between the enterprise and the local community. “Clean energy development is one of our core strengths. We hope to leverage our technical capabilities to advance rural revitalization efforts tailored to local conditions,” Yang says.

At present, the construction and operational costs of green air conditioner initiative are largely covered by the Hydrogeological Bureau, while local residents are only responsible for paying the electricity bill. 

Looking ahead, the Hydrogeological Bureau plans to build a zero-carbon tea factory and scale up the project for broader application.

Tangyang’s zero-carbon efforts go beyond the river-based green air conditioning system. A capsule-style homestay project—also developed by the Hydrogeological Bureau—was completed in January this year. The facility utilizes the bureau’s geothermal technology, extracting hot spring water from a depth of 1740 meters to support operations, forming an integrated cultural and tourism offering.

Looking to the future, the team aims to further integrate tea culture with hot spring tourism, promoting the sustainable development of the local cultural tourism sector through clean energy solutions.