Tucked in a grassy ridge cutting across the Small Family CSA Farm in La Farge, Wis., is a refrigerator so efficient it requires not a single watt of electricity, yet it can keep some crops chilly for months. It’s not some high-tech, Swedish-designed, solar-powered cooling unit. Just a good old-fashioned root cellar, kept cool through the summer months, and above freezing in the winter, by the soil surrounding it.
Shunning hulking and energy wasting refrigerated cold storage, Jillian and Adam Varney four years ago chose to build this two-room cellar for $10,000. Over time, like solar panels, it will pay for itself in savings – and in revenue for their small, organic farm. The hand-built produce closet, which includes a room kept extra cool with a small air-conditioner, allows them to extend their 220-member community-supported agriculture operation (CSA) into the winter months.
Root cellars are basically any storage area that operates on the earth's natural cooling, humidifying, and insulating properties. To work properly, a root cellar must stay between 32 and 40 degrees Fahrenheit and at 85 to 95 percent humidity. The cool temps slow the release of ethylene gas, halting decomposition. High humidity levels prevent evaporation loss, stopping your veggies from shriveling and withering.
Outmoded with the birth of the refrigerator and the 1950s kitchen, root cellars all but went underground, resurfacing briefly in the ’60s and with survivalists. Now, this tiny house movement for foodstuffs is experiencing a slow but certain renaissance as the local food movement gains momentum.