Our goal is to make a commercial-scale walk-in refrigerator that uses less than 10 Watts of power, built for under $1000. The refrigerator will be a well-insulated room in the basement of the Medway Community Farm’s farm-house, about 8 feet on all sides.
The refrigerator will function by freezing a large mass of ice in the winter and using that to keep the fridge-chamber cool for the rest of the year. The ice is contained in about 800 2-liter soda bottles, stacked up like firewood in a separate chamber behind the South wall. During the winter, a small fan blows cold air from outside past the bottles, freezing them. During the rest of the year, a temperature-controlled fan will blow cool air from the ice chamber into the fridge chamber, whenever the fridge gets too warm.
The Medway community farm will use the fridge to store vegetables. We will design the system to keep them between 34°F and 41°F and maintain a fairly high level of humidity.