The head of Germany's regulatory agency for energy has urged people to save energy and prepare for winter, fearing Russia might cut off natural gas supplies.
Federal Network Agency president Klaus Muller urged house and apartment owners to have their gas boilers and radiators checked and adjusted to maximise their efficiency.
"Maintenance can reduce gas consumption by 10 to 15 per cent ," he told Funke Mediengruppe, a German newspaper and magazine publisher.
Mr Muller said residents and property owners need to use the 12 weeks before the northern hemisphere's cold weather sets in to get ready.
He said families should decide "whether every room needs to be set at its usual temperature in the winter or whether some rooms can be a little colder".
The appeal came after Russia reduced gas flows to Germany, Italy, Austria, the Czech Republic and Slovakia earlier this month, as European Union countries scramble to refill storage facilities.
Gas, often supplied by Russia, is used to generate electricity, power industry and heat many European homes in the winter.
Russian state-owned energy company Gazprom blamed a technical problem for the reduction in natural gas flowing through Nord Stream 1, a pipeline which runs under the Baltic Sea from Russia to Germany.
The company said equipment being refurbished in Canada was stuck there because of Western sanctions over Russia's invasion of Ukraine.
German leaders have rejected that explanation and called the reductions a political move in reaction to the European Union's war-related sanctions on Moscow.
Vice chancellor Robert Habeck, who is also Germany's economy and climate minister and responsible for energy, has warned a "blockade" of the pipeline is possible starting on July 11, when regular maintenance work is due to start.
In previous summers, the work has entailed shutting Nord Stream 1 for about 10 days, he said.
The question is whether the forthcoming regular maintenance of the Nord Stream 1 gas pipeline will turn into "a longer-lasting political maintenance", Muller said.
If the gas flow from Russia is "to be lowered for a longer period of time, we will have to talk more seriously about savings", he said.
In the event of a gas supply stoppage, private households would be protected, as would hospitals and nursing homes.
"I can promise that we will do everything we can to avoid private households being without gas," he said.
"We learned from the coronavirus crisis that we shouldn't make promises if we're not entirely sure we can keep them."
He said his agency "does not see a scenario in which there is no more gas coming to Germany at all".
Earlier this month, Mr Habeck activated the second phase of Germany's three-stage emergency plan for natural gas supplies, warning Europe's biggest economy faced a "crisis", with storage targets for the winter at risk.
Australian Associated Press
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