An excavator on display at a showroom of Shanxi TZCO Construction Machinery Co., Ltd. in north China's Shanxi Province is fitted with a hydrogen tank, a core component that allows it to operate with zero emissions.

Shanxi, China's largest coking coal producer, generates large volumes of coke oven gas as a byproduct of coking, with hydrogen accounting for up to 60 percent of the gas. The province is also home to a dense cluster of steel and mining operations that rely heavily on construction machinery. That combination of surplus hydrogen and strong energy demand has created an opportunity to turn the byproduct into a valuable resource.

A hydrogen-powered excavator produced by Shanxi TZCO Construction Machinery Co., Ltd. is loaded onto a truck in north China's Shanxi Province. (Photo courtesy of the company) 

The company delivered its self-developed hydrogen-powered excavators and loaders in March, among the first such machines put into operation in the mining industry.

"Many assume switching from fuel to hydrogen just means swapping the engine," said Liang Junfang, head of the company's product verification and improvement center. "The real challenge lies in rebuilding the entire power system and adapting it to the equipment."

Fuel cells deliver steady output, but excavators require sudden bursts of power during heavy-load tasks. To bridge that gap, the company's research and development team built a buffer system combining batteries and supercapacitors to store surplus energy and release it instantly during peak demand. The system also uses voltage stabilizers to keep components working in sync.

Excavators produced by Shanxi TZCO Construction Machinery Co., Ltd. await delivery in north China's Shanxi Province. (People's Daily Online/Zhao Fang) 

The machines can now run for five to eight hours after just five minutes of hydrogen refueling, with zero emissions throughout operation. A TZ240 excavator operating 15 hours a day can save more than 500 yuan (about $74) in daily costs compared with traditional fuel-powered models, Liang said.

The company has also cut equipment weight by 8 to 10 percent using high-strength steel and wear-resistant alloys. Modular designs have boosted disassembly efficiency by 50 percent and raised the parts interchangeability rate to 85 percent. Smart systems enable predictive maintenance, extending equipment lifespan by more than 10 percent.

Shanxi TZCO Construction Machinery Co., Ltd. has been recognized as a national-level green factory for its comprehensive green manufacturing system and its progress in energy conservation and emissions reduction. Six subsidiaries of its parent company, Taiyuan Heavy Machinery Group Co., Ltd., have earned the same designation, making the group a leader in green transformation among Shanxi's equipment manufacturers.

Photo shows a national-level green factory in Hongtong county, Linfen city, north China's Shanxi Province. (People's Daily Online/Lu Pengyu) 

Shanxi has made the development of green factories a key driver in transforming and upgrading its manufacturing sector.

The province has established 144 national-level green factories, seven green industrial parks and six green supply chain management enterprises, spanning sectors including equipment manufacturing, coal chemicals, pharmaceuticals and casting.

National-level green factories contributed 30 percent of Shanxi's manufacturing output value in 2025, said Pan Haiyan, head of the Industry and Information Technology Department of Shanxi Province.