As Europe braces for energy shortages from Russian gas cuts, Japan's own energy crisis a decade ago offers survival lessons to households and businesses - such as dimming the lights and taking the stairs.
EU energy ministers on Tuesday approved a proposal for member countries to cut gas use voluntarily by 15% from August to March amid uncertain supplies from Russia due to the war in Ukraine.
Energy saving, or "setsuden", became a national project for Japan in the aftermath of the March 2011 earthquake and tsunami that triggered a meltdown at the Fukushima Daiichi nuclear plant.
In the weeks and months that followed, shopping centres switched off escalators, factories pared back assembly line times, and pachinko gambling parlours - famous for their flashing lights and noisy machines - were temporarily shut.
The attitude of many Japanese at the time was "We need to do something, otherwise, there's going to be a disaster," recalled Koichiro Tanaka of the Institute of Energy Economics, Japan.
Intense social pressure - the kind that has ensured almost complete public compliance with mask wearing during the Covid-19 pandemic - also played a part, he said.
Tokyo Electric Power Co, the operator of the Fukushima facility, lost about 40% of its power generation capacity.
In the immediate aftermath of the accident it issued its first-ever scheduled blackout and halted power in the capital area intermittently in the weeks to come. It eventually rebooted older, gas-fired and coal-fired plants.
In May that year, the government urged citizens and businesses in Tokyo and northern Japan to curb power by 15% at peak times during the summer. Similar measures are being taken again this year in Japan as it too grapples with tighter energy supply.
Most Japanese companies entered austerity mode as soon as the 2011 disaster hit, switching off lights and idling elevators. The environment ministry targeted an even bigger reduction of 25% through steps such as turning off more than half of its printers during peak hours, and asking workers to bring in their own cold drinks so it could unplug vending machines.
Professional baseball and soccer teams halted night games and moved matches to afternoons to reduce demand for lighting. Workplace managers raised thermostats and encouraged employees to embrace the government's "Cool Biz" campaign of wearing lighter clothes in the summer.
Automaker Nissan Motor Co rejigged factory shift times to ease the burden on the grid at peak mid-afternoon hours and convenience store chain Lawson Inc switched to LED light bulbs and added solar panels at many of its stores.
Public sentiment turned against nuclear energy and by late 2013 Japan idled all 54 of its nuclear reactors that had supplied about a quarter of the country's power, although a small number of those reactors have been since restarted.
To plug the energy gap, Japan turned to fossil fuels such as liquefied natural gas (LNG), coal and oil. LNG imports from Qatar surged after the disaster, more than doubling to 15.66 million tonnes in 2012 from 2010 levels.
The rise in energy imports was one of the factors behind Japan logging its first trade deficit in 31 years in 2011. The economy slid into recession in the aftermath of the quake and energy shortages, choking off a nascent recovery from the global financial crisis.
Gross domestic product fell 0.9 percent in the quarter during the accident, and was flat for all of 2011.
Differing voltage standards between the eastern and western parts of the country made even domestic load-sharing difficult, said Tanaka.
"In the case of the Europeans, since they are connected by grids, they may still have the sense of a last resort coming from somewhere," he said. "Here in Japan, we don't have that luxury. It's only us."