This month, temperatures in Britain reached a record 40.3 degrees Celsius, or 104.5 Fahrenheit, capping a brutal heat wave that scorched Europe and sent electricity demand soaring.
It came amid a war in Ukraine that has upended the global energy market.
The energy crunch prompted European Union nations to agree on Tuesday to reduce their gas consumption by 15 percent between now and next spring as officials prepare for Russia to cut deliveries of natural gas in the coming months.
Here are of some of the things countries could do to curb energy demand, and some of the potential pitfalls:
Adjust thermostats, starting in government buildings
Setting an air-conditioner just one degree Celsius, or about two degrees Fahrenheit, warmer could reduce the amount of electricity used by 10 percent a year, according to the International Energy Agency.
Nick Eyre, a professor of energy and climate policy at the University of Oxford, said that governments could set an example. The general public, he noted, might not respond well to politicians telling them how to live without making changes themselves.
Adjusting the thermostat lower in the winter by just one degree Celsius for buildings in Europe could save as much as 10 billion cubic meters of gas, equivalent to the annual gas demand of Austria.
Lower the cost of public transportation
Worldwide, incentivizing public transportation by making it cheaper and encouraging other mobility options, like walking or cycling, could save around 330,000 barrels a day of oil use, according to the I.E.A.
That number could grow if employers simultaneously provide flexibility in working hours or allow more work-from-home days.
Some countries in Europe are already doing this. Beginning in June and running through at least August, Deutsche Bahn, the German national railway company, offers unlimited public transport passes for the equivalent of about $9 a month, as part of plans to mitigate the effects of inflation. Ireland and Italy also cut public transport fares for certain groups, like young adults, students and workers.
One limitation: It would not be particularly effective in rural areas that don’t have robust public transportation.
Reduce speed limits, and make them stick
In theory, lowering the speed limit on highways could significantly reduce fuel consumption for cars and trucks, according to a report from the International Energy Agency. A number of countries and urban areas already have speed limits in place to reduce congestion and pollution.
If speeds limits on highways were reduced by at least 10 kilometers per hour, or roughly 6 miles per hour, advanced economies could cut oil demand by at least 290,000 barrels of oil a day, the report said.
As a practical matter, though, it can be difficult to implement a national speed limit and to get enough citizens on board to achieve significant results. The United States tried to do it in 1974, introducing a national speed limit of 55 miles per hour for automobiles, buses and trucks after OPEC cut oil supplies to the country, estimating that the limit could save 200,000 barrels of gasoline a day. Several European countries also reduced speed limits.
At the time, officials believed the limit would reduce gasoline consumption by 2.2 percent, but actual gasoline demand remained relatively flat in the years following. Motorists widely disregarded the law, and some states that opposed the rule handed out only modest fines of $5 to $15 for people caught speeding.
Get public outreach campaigns right
Well-designed public awareness campaigns can motivate people to take measures to reduce their own energy use, but poorly designed campaigns that don’t find the right tone and message can fall flat.
Some energy conservation campaigns are more successful when they emphasize how people can save money with their actions; others do better when they take an environmental approach or make moral appeals about good citizenship. In many cases, governments could take advantage of social media to tailor different messages to different audiences.
It’s important to not only think about the message and how it is conveyed, but also about the messenger. If citizens don’t perceive the government as a credible authority, they’re less likely to believe the message, an I.E.A. report said.
The best campaigns strike a balance between urgency and agency.
“You can’t just put information out there and expect people to change their behavior overnight,” said Brian Motherway, the head of the energy efficiency division at the International Energy Agency. If you employ behavioral scientists and communications experts and take the time to design an intentional campaign, he said, “you can really get it right.”
“You can find ways to engage with citizens in a way that really empowers them and motivates them to act.”