The more I look into solar powered emergency refrigeration, the more frustrating it is getting. Specifically the cost of the 12V DC powered freezer/fridge when comparing AC powered refrigeration to DC powered and even the design of the units themselves and the lack of flexibility for multiple electrical power options i.e. a DC refrigerator just needs a switch mode AC-DC PSU to power the DC motor. The SunDanzer refrigerator seems to be a remarkably efficient design but even with this Freezer, I would want the SunDanzer freezer to have the facility to operate as a refrigerator as well (especially for the asking price) due to the fact that the temperatures they operate should be programmable i.e. a simple PIC based, 3 term controller be implemented for variable temperature control would only cost a few dollars to implement. This would allow the Freezer (-18C) to operate as a refrigerator (+2 to +6C) if solar power outputs are limited. (it would allow the Freezer contents to be consummed within 3-4 days during a major power grid failure then allow the Freezer to be operated as a refrigerator with a 60 Watt PV solar panel and Xantrax 300 portable powerpack battery. This would help reducing the spoilage of food)

http://www.builditsolar.com/Projects/Conservation/chest_fridge.pdf

I cannot even find a supplier for the SunDanzer or even an equivalent design within the UK. Surely its not beyond most manufacturers wit to use a DC motor with an optional AC-DC PSU (for grid use) instead of an AC motor just for the added flexibility in the chest freezer design. Even an easily made cosy down bag designed to fit over a cheap conventional chest freezer retrofitted to act as a fridge with a baffled zip around the edge of the top lid might be worthwhile to save energy costs and increase efficiency (to reduce thermal fridge losses) for Solar PV operation in an emergency. (although a pure sinewave battery inverter might be required for the AC motor)