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Set up refrigeration and cold storage

A fridge and freezer run 24 hours a day, so their efficiency strongly affects battery size. Pair efficient appliances with passive cold storage.

How

1. Choose the most efficient fridge and freezer you can find; chest freezers lose less cold air when opened.
2. Set the fridge to about 3 C (37 F) and always below 4 C (40 F), and the freezer to -18 C (0 F), as DOE recommends.
3. Keep appliances full (add water bottles or ice) and let hot food cool safely before storing.
4. Place appliances away from heat sources with space for air around the coils.
5. During a power outage, a closed full freezer keeps food safe for about 48 hours.
6. Hand off root cellars and passive cool stores to the living module.

Safety: Discard food that has been above 4 C (40 F) for more than 2 hours.

Do these first

• power-1

Sources

1. Refrigerator and Freezer Use and Temperature Tips. U.S. Department of Energy, Energy Saver, accessed 2026-11

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