For the past few weeks, the US media have been filled with the sound of commentators tearing their hair out and beating their breasts.
The source of their distress is a report published by the Pew Charitable Trusts entitled 'Who's winning the clean energy race?'
According to the report, last year China almost matched the US on the renewable energy leader board, with 52.5 gigawatts of installed capacity, compared with America's 53.4 gigawatts.
(A gigawatt, for those of us confounded by the ever-growing array of Greek prefixes, means one billion watts. So 52.5 gigawatts is enough power to light 875 million of those 60-watt incandescent light bulbs we are not supposed to use anymore. Clearly that's a lot of watts.)
What's more, according to Pew, China is investing much more heavily in clean energy than the US. Last year, China poured an enormous US$34.6 billion into the sector, nearly twice as much as the US.
As a result, the media have been filled with howls of anguish lamenting that the US is being beaten hollow by China in the battle for clean energy dominance, as if saving the planet were an arms race which America must win or perish.
Let's leave aside the thought if China - the world's largest emitter of greenhouse gases - is now the biggest investor in clean energy, then that should be a source of encouragement rather than a cause of lamentation.
And let's not bother to consider that because of the big difference in purchasing power - US$1 billion buys you 30 per cent more in China than it would in the US, according to one recent estimate - it is likely China has effectively been out-spending the US for years.
And let's also forget that for some strange reason the Pew report doesn't consider energy generated by large hydro projects like China's Three Gorges dam to be renewable (although small projects are counted as clean energy).
But even ignoring those considerations, there are other problems with the Pew report and the media's reactions to it.
Thanks to government subsidies, China is certainly investing heavily in cleaner electricity generation, notably in wind and hydro-electric power capacity. By the end of this year, according to Xinhua, cleaner energy - hydro, nuclear and renewable sources like wind - will make up 26 per cent of total installed capacity.
The big catch is that installed capacity doesn't necessarily have much to do with actual power output. Hydropower, for example, is seasonal. Output during the dry winter months is typically half that during the wetter summer. As a result, hydro plants spend most of the year operating far below their full capacity.
Power output from wind-farms is highly variable too. Given the unreliability of the wind, turbine output is typically reckoned to be just 30 per cent of capacity, although in some cases the figure is more like 20 per cent.
In China, the picture is further distorted. Much of the vast investment in wind energy has gone into turbine production facilities, which has led to considerable overcapacity.
According to reports last week, some 40 per cent of the mainland's wind turbine production capacity has been shut down for want of customers. Meanwhile 20 per cent of installed wind turbines are sitting idle, because although they have been erected, they have yet to be connected to the distribution grid.
As a result, rather than looking at installed power generation capacity, it makes far more sense to look at electrical energy actually generated.
This gives a very different picture. According to Pew, China boasted a wind capacity of 22 gigawatts last year, which means in theory it could have generated a maximum of 193,000 gigawatt-hours of electrical energy from wind.
According to official output data, however, China generated just 56,000 gigawatt-hours of electricity from all sources other than thermal, nuclear or hydro. In other words, at most, all those wind turbines could have been operating at no more than 29 per cent of capacity.
As a result, despite all the clean energy investment, more than 80 per cent of China's electricity output last year was generated by thermal plants, almost all of them coal-fired. In contrast, the US generated just 45 per cent of its electricity from coal.
Still, that should hardly cheer up the breast-beating commentators. The US may be cleaner in its energy generation, but both countries are still far too dirty.