idle production capacity

基本解释

Production capacity is grossly underused with many idle workers and machines obvious to any visitor to the state factory.
由于大量工人无所事事，大量机器闲置一边，来参观这家国有工厂的人很容易就能看出工厂生产力低下。
cai.jnu.edu.cn

Also, Chinese idle production of steel is greater than the production capacity of Japan and South Korea combined.
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Unlike other metals where production has been taken offline, there's no idle capacity in the nickel industry.
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He recently threatened to expropriate some 700 idle firms, along with more than 1, 000 working below capacity, unless their owners resumed full production.
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