Domestic hot water is provided mainly by a heat pump using exhaust air from the composting toilet.

家庭生活热水主要由以沼气为燃料的热泵提供的，沼气是由带发酵装置的厕所产生的。

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After the toilet first broke down last week, the station's crew replaced its pump with a spare they had on board.

NPR: Space Toilet Awaits Repair Mission