PENGLAI, China — When Chinese authorities declared three years ago that they would limit the use of coal energy and canceled more than 100 coal power projects, climate campaigners cheered what seemed to be a sweeping policy reversal for the world’s largest greenhouse gas emitter.

They may have celebrated too soon.

Here on the Shandong province coastline, cranes perched over a half-built smokestack and two furnaces show how once-suspended coal power projects are being revived — and entering service — across China, tilting the balance of coal power worldwide and worrying climate scientists.

In the past two years, China has expanded its coal fleet by 43 gigawatts — roughly the entire coal-fired capacity of Germany — according to Global Energy Monitor, a group that tracks construction in the Chinese power industry using public announcements and satellite images.

Excluding China, global coal power capacity would otherwise be dropping as countries in Europe and elsewhere decommission old facilities and switch to other energy sources, the group said in a report released Wednesday.

“To meet Paris climate goals, climate scientists say global coal power needs to be reduced 70 percent by 2030 and phased out completely by 2050,” said Christine Shearer of Global Energy Monitor. “China’s proposal to continue adding new coal power capacity through 2035 flies directly in the face of these needed emission reductions, and jeopardizes global climate goals.”

Researchers say China and ­climate-change efforts worldwide are facing a crucial juncture. After years of progress with air quality and declining coal consumption, China’s leaders in recent weeks have signaled a subtle shift as they manage the slowest growth levels in almost three decades and a damaging trade war with the United States.

In a departure from earlier speeches, Premier Li Keqiang last month urged the coal industry to play a role in securing the country’s energy supply. Weeks earlier, top officials said they would relax air-quality controls this winter, perhaps to buoy important but dirty drivers of economic activity, such as steel mills and construction. And at least 40 new coal mines have been approved this year, China’s energy administration told reporters last month.

Researchers who examine Chinese policy say a vigorous debate is taking place behind the scenes. The country’s Communist Party rulers are consulting industry and academia to formulate a comprehensive development blueprint, known as the five-year plan, to take effect in 2021.

“The coal industry’s propaganda is stressing that it’s imperative to maintain coal’s primary position in China’s energy mix, and that narrative is now back in favor,” said Yixiu Wu, a researcher at Chinadialogue, an environmental nonprofit in Beijing. “The trajectory is worrying because we’re right in the window when China is shaping its 14th five-year plan.”

China’s current five-year plan has set a coal-power cap of 1,100 gigawatts. But some in China’s energy industry are pushing for that cap to be raised to 1,400 gigawatts in the next plan, researchers say. Global Energy Monitor says China’s coal power capacity must decline beginning in 2022 for China to keep global warming under two degrees Celsius (3.6 degrees Fahrenheit).

At the central government level, Chinese leaders for years have trumpeted their commitment to shift to green growth after relying for decades on low-value manufacturing and resource-extractive industries that caused thick smog and polluted soil. China’s leader, Xi Jinping, positioned himself as a champion of sustainability after signing the 2016 Paris climate agreement, pledging that the country’s carbon emissions would peak by 2030.

Propaganda officials these days produce books and classroom materials to promote Xi’s “Ecological Civilization” concept with collections of his thoughts and sayings, often accompanied by imagery of lush mountains and blue rivers.

The picture on the ground is murkier. To be sure, China’s coal consumption peaked in 2013 and gradually declined, although it has ticked upward again since 2017.

In 2016, China’s top economic planning authorities, worried about the frenzied pace of new coal power plant construction and air pollution, called for nearly half of China’s provinces to stop building the facilities. In January 2017, central government energy officials froze 103 projects, including the 2,000-megawatt Zhongxing power plant in Shandong province, in eastern China.

Just two months later, provincial authorities gave the go-ahead anyway. Shandong officials approved Zhongxing as an “energy efficiency demonstration project,” making it exempt from the national freeze.

Elsewhere in the province, other coal projects roared ahead. By the time a central government environmental protection team inspected Shandong in 2018, it found a local company that had, in the space of five years, illegally built 45 coal power facilities that produced the equivalent of Australia’s coal-fired capacity. That disclosure forced the company to lay off 180,000 workers.

Shearer, from Global Energy Monitor, said Chinese local officials were under tremendous pressure to meet economic targets and often looked the other way if coal facilities were generating jobs.

“These are massive projects,” she said. “Once a coal plant has been permitted, there’s momentum and political pressure to let that plant go through to commissioning.”

In its report released this week, Shearer’s group named two dozen plants that have resumed construction, from Inner Mongolia in the north to Guangdong province bordering Hong Kong. Upon completion, they would add about 150 gigawatts, nearly the entire existing coal power capacity of the European Union.

In Penglai, the emerging silhouette of Zhongxing’s coal plant seems almost out of place rising next to the beach. Giant wind turbines dot nearby ridgelines — another example of Shandong’s bet on the energy industry. In the gently rolling hills, French-style chateaus, including one owned by the Rothschild family, produce award-winning wines.

The $1.2 billion project, according to its official website, is a “milestone demonstration project in the history of electric power development in China, indicating that China’s coal-fired power generation technology has reached a leading level in the world.”

Phones at Zhongxing rang unanswered, and the company could not be reached for comment. But construction appeared stopped for the winter, and rows of temporary housing for hundreds of builders seemed empty, during a visit this week. Security guards and residents said work stopped only recently and was in full swing earlier this year, when teams broke ground on two out of four furnaces for the project’s first phase.

Accounts in local media and the company website have reported swift progress. In an April meeting, Zhongxing’s chairman, Li Maoyin, exhorted his construction teams to redouble their efforts.

“The second half of 2019 is the peak of civil engineering and facility installation,” he said. “The construction period is very urgent.”