By Quentin Sommerville
BBC Shanghai business correspondent, in the Lijiang Valley
The local speciality in the Lijiang valley, in western China, is fatty pork. It's not terribly good for you, but it is delicious.
Composting dung into fuel is just part of China's environmental plan
So it's not not surprising that the people here value their pigs. And they've now found a use for them apart from in the cooking pot.
Lijiang is rural China at its most pristine, with families living in traditional courtyard houses and working the fertile land at the foot of the jagged and snow-capped Yulong mountain.
The pigs who live with them inevitably produce a lot of muck.
But muck contains lots of energy, and some 10,000 families are putting it to good use: shovelling it up and putting it in a pit in their backyards. There it stews, brewing methane gas which flows along a small rubber pipe directly into the kitchen stove.
For these families, there's no need for firewood and a good deal less smoke.
Change of direction
And this last benefit puts the people of Lijiang, and their pigs, right in step with the new message from Beijing.
China's leaders are demanding that China become a good deal greener. Economic growth at all costs will no longer do.
This new-found ambition has got Western - and Chinese - companies licking their lips in anticipation.
A quarter-century of breakneck development has left the environment in China on the brink of collapse.
About three-quarters of the rivers in the cities have water that is undrinkable and the quality of the air is often little much better. Chinese people are beginning to protest about the dangerous waste around them.
The leadership in Beijing is sitting up and taking notice.
The eleventh economic plan, neatly rubber stamped by the National People's congress this month, makes some incredibly ambitious environmental promises.
China will cut energy use by a fifth over the next five years - even while the economy continues to grow at a blistering pace.
Industrial pollution will fall by a tenth, and water consumption by factories down by almost a third.
No-one would doubt that these are bold commitments. But will they happen?
The announcement of a tax on disposable chopsticks is one highly visible part of the plan. It's designed to safeguard the 1.3 million cubic metres of Chinese timber lost to chopstick production every year.
Similarly, a 12% increase in tax on large-engined cars is intended to make drivers think twice about buying a gas-guzzler.
Jorge Mora, who runs the Asian arm of French water and environment group Veolia, says China is serious about its clean-up plans.
China is looking to its rivers for much of its energy needs
"China is taking very harsh policy decisions to improve the environment," he says. "We're now working in 60 different Chinese cities, building sewage plants and cleaning up waste. The Chinese are serious about this, both at national and local level."
In Shanghai, his company runs an incinerator that turns the city's rubbish into electricity.
It may be French-run but it is Chinese owned, and an increasing number of Chinese firms are building green technology of their own.
They hope to capitalise on the country's doubling of its commitment to renewable energy: the target is that 15% of all power will come from renewable sources by 2020.
But there are many hurdles along the way. China's view of renewable energy differs from most. The majority of its so-called green power will come from massive hydro projects like the Three Gorges Dam.
Indeed, there's hardly a river in China that hasn't been dammed, and work has already begun on projects that will increase the country's hydro power by 80% over the next five years.
And China is largely relying on the private sector to repair the damage of the earlier industrialisation - the environmental protection agency employs only a couple of hundred people.
The more basic problem is that the policy shift practically turns country-wide practice on its head. For the past two decades, all that has mattered to officials across China has been economic growth, and getting them to switch to a more planet-friendly view will not be easy.
Environmentalists - like Xue Ye, executive director of Friends of Nature in Beijing - are sceptical about the country's new green plan.
"The concept and slogans are good," Mr Xue says. "But it still has to be put into action at local levels or the environment will suffer more.
"The World Bank says the environmental damage costs us about 7% of our GDP. The highest figure I have seen is 18%. That wipes out our economic growth. The growth we have is inflated - it's not sustainable."
China's new green vision is born in part from a fear that its people will no longer bear their land and rivers being ruined.
It's an ambitious plan, and one without precedent. But the environmental scars here run deep, and will not be easily shifted.
And China is still refusing to pause for breath in its race for economic growth - making it all the more difficult for China to return to nature.