Yang Fuqiang, a China expert with the US National Resources Defence Council, has little patience with arguments the world's biggest emitter of carbon dioxide should leave it to richer nations to take the lead on tackling climate change.
Already the source of a quarter of global emissions, by 2020 China will emit as much as the US, the European Union and Japan combined on current trends, Dr Yang said.
True, China's per capita emissions lag more developed nations, but in "five years or sooner" it would l reach EU averages.
And as for the argument China is not responsible for the cumulative CO2 produced by earlier industrialisers? By 2030-35, China will exceed EU's historical emissions.
"Whatever the excuse or criteria, China will soon reach it," Dr Yang said.
His comments, made to the annual Clean Energy Week conference this week in Brisbane, are borne out by the US government's International Energy Outlook 2013 report released on Thursday.
While renewable energy and nuclear power are the fastest-growing energy sources - expanding at a 2.5 per cent annual clip - fossil fuels will still supply 80 per cent of global energy use until 2040, the report said.
Energy-related CO2 emissions will jump from 31 billion tonnes in 2010 to 45 billion tonnes by 2040. China now accounts for 44 per cent of coal production and its share will peak at 52 per cent in 2030.
Dr Yang, though, argues changes within China will curb coal use faster than many predict. Public anger over urban pollution and the impact of coalmining on water supplies is already stoking government efforts to expand renewable energy.
China's solar energy firms, facing steep anti-dumping tariffs in the US and Europe, will also be forced to cut their 90 per cent reliance on exports.
Dr Yang predicts China will have 300 gigawatts of installed wind power by 2020, 50 per cent higher than Beijing's 200-gigawatt target. Solar photovoltaic capacity will be more like 100 gigawatts by then, double the current goal.
In terms of shaping global energy, China's renewable energy surge would rank with the US shale gas boom and Europe's efforts to decarbonise its energy, Dr Yang said. "For the next few decades, you will observe renewable energy developing very rapidly in China."