Whisper it, but could China be about to turn an environmental corner after more than three decades of filthy economic growth? Hopes for a cleaner future are rising ahead of a national blueprint to tackle pollution, waste and champion renewable technology.

The five-year plan, due in March, is being hailed as the greenest strategy document in the country's history. Sceptics warn that one environmental threat – industrial pollution – may be replaced by another – excess consumption.

The five-year economic plan, once an arcane exercise in communist fiat, has big implications for the outside world. It could affect the colour of the sky, the planet's temperature and the welfare of billions of people beyond the jurisdiction of the country's mandarins.

An army of cadres, officials and academics have spent years laying groundwork for the plan – the 12th since Mao Zedong started Soviet-style strategising in 1953. They have one of the world's most ambitious administrative tasks: plotting a course for a continent-sized nation, a 1.4 billion population and a $5 trillion economy that is growing at double-digit speed every year.

It has never been more important to the global environment.

China is the world's biggest greenhouse gas emitter, number one energy user and arguably the most polluted nation on earth. The International Energy Agency noted that Europe's plan to extend 1990-2020 carbon dioxide cuts from 20% to 30% would equal only two weeks of China's emissions.

The final document will include measures to curb pollution, promote clean technology and initiate an environment tax, the Guardian understands.

"The environment tax is going to happen. This is evident in the proposals for the next five-year plan," said Ma Zhong director of the school of environment and national resources at Renmin University. "It is likely to be levied nationwide, but there is also a possibility it will initially be introduced in selected regions."

Other radical measures still under discussion include a possible cap on energy use and a shift away from GDP-based performance evaluation, academics and government advisers say.

Hu Angang, economics professor at Tsinghua University and a consultant on the plan, said he advised the government to set a cap on energy consumption, to influence when China's emissions might peak. With existing targets, this is not likely before 2030, by when carbon dioxide output will have more than doubled. Hu is pressing for more rapid reductions.

"For the first time, we will see a new model pioneered by a country that is not yet developed. This is a historical, critical change," he said. "The new five-year plan is an opportunity for China to lead the green revolution, which will de-link growth and carbon dioxide emissions."

It is far from certain his radical proposal will be adopted, though several NGOs and international institutions said the suggestion has had surprising traction.

The five-year plan will see a growth in both black and green power consumption. Even as coal use rises, Beijing will blaze further along the trail towards a low-carbon economy. Its wind power generating capacity has doubled annually for four years and in 2010 became yet another field in which China surpassed the US to become number one. Seven of the planet's top 10 solar panel makers are now Chinese.

The focus in future is likely to be nuclear energy, forecast to increase tenfold over the next 10 years, and hydroelectric power. Last month, the National Energy Agency said China plans to build an additional 140 gigawatts of hydropower capacity in the next five years, though this will have a dire impact on ecologically crucial sites.

The country's high-speed rail network – non-existent in 2008 – will be bigger than the rest of the world combined within two years. According to one domestic carmaker, China will soon unveil plans for 10m electric car charge-and-park places by 2020. In these and other fields, such as eco-city development and public transport construction, the five-year plan is likely to set ambitious spending targets.

Last year China invested $34bn in clean technology, compared to $18bn by the US. The contrast – which shocked many in Washington – is partly explained by different political systems, vested interests and stages of development. While the US is dominated by big oil and big money, China is run by big hydro and big brother – a dictatorship of engineers.

The "scientific development" policy of President Hu Jintao, who started his career working for Sinohydro, the world's biggest dam builder, recognises the challenges posed by climate change and the investment opportunities of renewable energy. It has been far less successful in curbing the dirty side-effects of industrial development.

Deborah Seligsohn of the World Resources Institute said there was a clear difference between China's record on pollution – where it lags far behind developed nations – and renewable technology, where it is ahead in many sectors.

"In clean energy, China is busy setting themselves up as a world leader. If they meet their most ambitious targets for 2020, they'll have the most wind, the most nuclear and the most hydro," she said. "But China is still playing catch-up on pollution. The air quality in Beijing does not exactly feel like London or New York."

That too should change. Sharp northern winds have helped Beijing to start this year with a record stretch of "blue sky" days.

A longer term solution to the smog shrouding many Chinese cities will be tighter factory and vehicle controls. Last week, the government said it would widen pollution reduction targets by adding nitrogen oxide – roughly a third of whichcomes from vehicle exhausts – and ammonia, a source of water contamination from chemical and textile plants.

Cities including Shanghai and Beijing have begun restricting car ownership. The authorities have also taken positive steps on the release of environmental data. For the past two years, the only real-time, publicly available air pollution monitor in Beijing was provided by tweets from the US embassy. From last month, up-to-the-minute air and water data from more than 100 cities in China has been available on the website of the environment ministry.

Green technology and pollution controls should improve the quality of the air and water, but they do little to ease the bigger environmental threat from depleting wildlife, ecosystems and natural resources. Each year northern China faces a shortfall of 40bn cubic metres of water, forcing ever deeper drilling into non-replenishable aquifers. To address this, China plans to cap water use and double spending on water conservation projects.

Government advisers say environmental talk will be greenwash unless local officials are persuaded to rethink their growth-at-all-costs mentality. Pan Jiahua, the executive director of the sustainable development research centre at the Chinese Academy of Social Sciences, expects this to happen naturally.

"GDP growth will have to be slowed down," said Pan. "This is somewhat natural. In Shanghai there is no more land available for development. In the steel industry, we have the capacity to produce 750m tonnes, which is 40% of the global total. There is no need to grow further."

While double-digit expansion has been the norm for the past five years, Pan expects the next target to be 8 or 9%. The plan will place greater priority on protecting arable land, food security, wildlife protection and the "ecological restoration" of areas damaged by construction of roads, rail and other infrastructure. Together, these would mark a turning point for China's environmental degradation. "In the 12th five-year plan, we will go beyond the peak and start to go down," he said.

That is optimistic. Previous attempts to give nature a breather by slowing the economy failed spectacularly. For the 10th and 11th five-year plans, the government aimed at 7-7.5% growth, but this was treated as a floor rather than a ceiling by overzealous local officials, who see GDP as a key measurement to compete with rival regions, get promoted and secure bribes. As a result, the economy surged forward at double-digit pace for most of this period – with dire consequences for coal consumption, pollution and habitat destruction. Once again, provincial governments appear unwilling to throttle back. Figures published late last month indicate most plan to double their GDPs during the next five years.

To tackle this problem, planners are considering another radical measure, to de-link GDP figures from cadres' performance evaluation. This may prove a step too far. While there is widespread praise for the proposals unveiled so far, there is scepticism about the government's ability to overcome business groups and corrupt officials who have benefited from growth.

"We are expecting to see a truly green five-year plan, which for the first time will contain really detailed measures and teeth in it," said Yang Ailun of Greenpeace. "The next five years will be the defining moment for China's environmental movement. There will be more disasters and more of a struggle to impose tougher regulations. Local interests groups have grown quite strong. They won't accept change quietly."

Ma Jun, of the Institute for Public and Environmental Affairs, said the government would take a big step forward if it set absolute limits on pollutants and resource consumption, rather than the incremental, economy-linked targets seen until now.

"This is the first major effort to translate words into actions. Before the government set targets and talked of improvement, but this is the first really major effort to integrate that into an economic plan. They should get credit for that," said Ma.

China still had a long way to go, given the appallingly low level from which it starts and the lack of many of the tools used to improve the environment in the west, such as a strong civil society and regulatory obligations for factories to disclose a toxic release inventory.

"I don't consider this a turning point," said Ma. "We haven't seen air and water really get clean yet. The measures under discussion are not sufficient at all. "

Beijing's claims to have turned over a green new leaf are also weakened by the continued destruction of the nation's ecosystems. Last month, the boundaries of the last fish wild sanctuary on the upper reaches of the Yangtze river were redrawn to make way for a dam that showed, say conservationists, the authorities lack a protection baseline. This highlights the greater longterm environmental threat facing China from the unsustainable use of resources, already visible in the depletion of water systems, biodiversity, energy, soil quality and arable land.

To deal with this, environmentalists say even the most progressive top-down policies need to be balanced with greater awareness at the grassroots otherwise China will follow the west in looking clean but consuming dirty.

"I'm hopeful about the next five-year plan," said Li Bo of Friends of Nature. "The government is prepared to go further than before. But we should do more. Until now, low carbon concepts have been introduced only for industry. In the future, I hope those ideas can be adopted in the community so we see a change in lifestyles."

• Additional reporting by Cui Zheng, Liu Yang and Han Cheng