BEIJING - Pi Heyang gingerly closed the door of his first car-to-be. Then, he ran his hand slowly along the shiny hood, touching the Chinese-made Tianjin Weizi sedan as delicately as if it were made of gossamer.

"This will change our lives," the Beijing bus driver said solemnly while his wife and young son stood at his side in the dealer's showroom.

Several miles away through Beijing's smoggy streets, an exhibition hall was jammed with thousands of people perusing booths with displays for new homes in suburban subdivisions. Videos played, dancers gyrated, and neon signs in English touted developments with names such as "Rich Garden" and "Canal Side Upper Strata Life."

"We want space, greenery, freedom," said Han Yu, a mobile phone salesman, after he and his wife signed papers to buy a three-bedroom condominium on Beijing's eastern outskirts for $105,000. "This is it."

This is the new Chinese Dream: cars and suburbs. Like the American counterpart, it is good news for many people - but perhaps bad news for Planet Earth. The same economic boom that is catapulting millions of Chinese each year into the middle class has made their country the world's fastest- growing source of the greenhouse gases linked to global warming.

As China's thirst for fuel helps push world oil prices to record highs, the country is emerging as a key factor in the debate over climate change - as well as a wild card that could determine the health of the world's economy.

Chinese leaders acknowledge global warming as a serious problem, and they have begun a concerted campaign to cut the country's greenhouse gas output, which is largely driven by energy consumption. The government is spending billions of dollars - nobody knows exactly how much - to increase energy conservation, shut fume-belching factories and reduce power plant emissions. At the same time, however, the resulting efficiency improvements have been outpaced by unrelenting growth in automobile use, power generation and industrial activity.

Although the Chinese government does not publish data about carbon emissions, most foreign analysts estimate that the country's carbon dioxide emission levels are now second only to the United States worldwide and are growing by anywhere from 5 percent to 10 percent a year, the fastest increase of any major nation. China is expected to overtake the United States for the No. 1 spot by 2025, with its share of total world greenhouse-gas output rising from 12 percent to 20 percent during the period.

Under the Kyoto Protocol, China and other developing nations are exempted from the mandatory cuts in emissions of global-warming gases that rich nations must obey. Chinese officials say such limits would prevent them from rising from poverty, and they point out that rich industrialized nations are responsible for the vast majority of global-warming emissions.

The Bush administration says China's exemption is unfair, and it is one reason that President Bush withdrew the United States from the Kyoto Protocol in 2001. Global warming is a top agenda item at the summit of the Group of Eight richest industrialized nations opening today in Scotland. The other seven members of the G-8 have promised to adhere to the Kyoto treaty.

Administration supporters say China's economic boom is fueled by profligate waste. China uses three times more energy per dollar of its gross domestic product than the global average and 4.7 times more than the United States, according to a recent study by the U.S. Department of Energy.

But Beijing officials defend the government's record.

"China wants to do its part against global warming, and we have taken many actions," said Zhou Dadi, director general of the Energy Research Institute, the central government's main policy agency on the subject. He cited several key steps in recent years, including these:

- A new law was approved in February to support the adoption of renewable energy sources such as wind and small-scale hydroelectric plants.

- Widespread energy-saving standards have been enacted for household appliances.

- Auto emissions standards will be stiffened by 2007 to a level tougher than current U.S. rules.

- Construction has started on nine high-speed passenger railway lines - the nation's first - to connect major cities.

Yet Zhou admitted that these moves were counteracted by broader economic forces.

"In the media there are lots of ads trying to convince people to adopt some kind of American life, a fancy car, a very big house," he said. "This is what everyone wants now. It is part of development; it is a historical process. Energy efficiency is a function of this."

(Distributed by Scripps Howard News Service, http://www.shns.com.)