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Kiwi drug dealer Stephen Royds could successfully have kept his dead girlfriend frozen, but he would have been working hard to do it.
International Cargo Exports Auckland branch manager Hein Mackay told the Weekend Herald 15kg of dry ice could be sufficient to keep an average-size woman frozen in a coffin-size compartment.
Royds was arrested last week after police found the body of Monique Trepp, 33, packed in dry ice in a large container in a California hotel room.
It is believed she could have been dead for up to a year.
The chemical - frozen carbon dioxide - deteriorates quickly, and Royds would have had to "top up" his improvised chiller "every two to three days".
"You wouldn't just put it on and leave it there for a month."
The product is available in this country in slabs, pellets or 5kg blocks, which cost about $7 each.
Dry ice is used to keep products chilled during export, but is more than capable of holding meat at the minus 18C required to keep it frozen.
The chemical is a solid at about minus 70C, and can be maintained as a liquid at about minus 18C. It does not, however, pass through a liquid state while reverting to a gas.
Anything stored in the chemical must also be protected from direct contact or "the major problem would be freezer burn, for sure", Mr Mackay said.
If Royds had kept the supply of dry ice constant, there is no reason why anyone would have detected his gruesome refrigerator.
"I have no idea how long a body should last in a freezer ... but I have had stuff in my freezer over a year. They don't just disappear, and they don't really start to stink until they are taken out and start to thaw out."
Supagas chief operating officer Gary Chapman said Royds would have to have made sure his chiller was not airtight.
Dry ice expands as it returns to gas, and could explode if kept in a sealed container.
