This is a very efficient electric cooler based on the free piston Stirling cycle that will maintain freezing temps even in a hot car. The power consumption is only 24 watts. It’s quiet, lightweight and works great. It’s more practical than the portable compressor or propane based freezers. According to Cool Tools, these coolers are quite reliable and last many years. The cooler runs on either 12v or 110v and has a 26 quart capacity.

Available from CostCo for $390.

These Coolmatic Waeco coolers are built with the Danfoss BD35F
compressor from Denmark, which means they run extremely efficiently on 12/24V
or AC power.

The 28 gallon model above consumes only 65 watts on average (45 watts on 12V
DC). You can get an insulating protective cover to make them even more efficient.

The coolers also have a control panel where you can set the exact cooling
temperature you desire.

This means the food contained within them can be kept icy cold for two days
straight on a single 80aH battery.

Purchase from: Coolmatic.Net ($400-772)

Energy Consumption: 18 or 24W DC
Dimensions: 12" H x 12" L x 9"
Weight: 2 lbs.
Best Price: $202 (Alternative Energy Store) or $259 (Southwest
Solar)

Notes from Manufacturer:
World’s lowest energy using cooler. Evaporative cooling for RVs, boats, cars,
tents and small rooms at a fraction of typical air conditioning energy costs.
Cools hot dry air as much as 35 degrees F. Connect to DC battery, cigarette
lighter receptacle, or solar module. Lightweight and portable-use for camping
and backpacking. Doubles as a good humidifier. 200 CFM. Uses 1 to 1-1/2
quarts of water per hour. Warranty: 5 years on highest efficiency CelDek(tm)
pad, 1 year on everything else.

Although not the most efficient cooler, we like the fact that this
cooler can be powered by so many energy sources.

Notes from Manufacturer:
Large enough to hold six 6-packs. Lightweight
and compact with rugged turquoise plastic exterior. Comes with ice cube tray,
thermostat and push button piezo igniter. Works with three different power
sources: LP gas (disposable 1-lb, low profile canister fits in back of fridge),
12-volt DC, or 120-volt AC.

Best price: $419 (Lehman’s)