The song New York, New York, first performed by Liza Minnelli in 1977, described the city as a place that never sleeps, many of its eateries as well as a lot of transport open around the clock.

Now it is the United States that never sleeps, with millions of light bulbs perpetually lit up from east coast to west coast.

"I was amazed when I first noticed that Americans do not turn off their lights," said Cai Lilin, a Chinese student who studied in New York from 2013 to 2015, and witnessed this huge waste of electricity.

Once when Cai turned off the lights when she was leaving a classroom, a classmate asked her why she was doing so, she said. "And then she turned the lights back on."

The bright billboards of Times Square both dazzled and shocked her, she said, and she was offended by the fact that they stayed lit up from dusk till dawn. "Look at all those office buildings, shopping malls, schools－I just can't understand why they want to leave all the lights on. Is this so people can see in the dark? But isn't that what streetlights are for?"

Cai, who now lives in Shenzhen, Guangdong province, said the US is simply wasting electricity, and should have it cut off to "find out what it's like without it".

About 90 percent of coal consumption in the US was used for power generation in 2019, the US Energy Information Administration said.

At the COP 26 climate summit in Glasgow, Scotland, US President Joe Biden castigated China, Russia and Saudi Arabia for not showing up and said these countries "have lost an ability to influence people around the world". Their contributions to global climate change were insufficient, he said.

Obstacles encountered

However, Biden himself had turned up in Glasgow with empty hands, said Lyu Xiang, an expert at the Chinese Academy of Social Sciences. "In fact, Biden's domestic legislation that includes proposed climate change measures has encountered great obstacles."

There should also be big question marks over some of the pledges the US has made, Lyu said, because Biden has been unable to gain total support for them even within his own party.

Electricity use in the US last year amounted to 3,801 billion kilowatt-hours, while that of China was about 7,510 billion kWh, the German market data aggregator Statista said.

However, the World Bank said every US citizen consumed 12,994 kWh in 2014, ranking 10th among hundreds of countries and economies, while the corresponding figure for China that year was just 3,927 kWh.

A recent UNEP-backed report said the US plans to increase fossil fuel production over the coming decades, and campaigners have said the US has had far more cumulative emissions since 1850 than the likes of China and India, which have industrialized only relatively recently.

Xie Zhenhua, China's special envoy for climate change, said the US withdrawal from the Paris Agreement five years ago had hindered progress toward its goals.

"Five years have been wasted, and now we have to make up for lost time."