CHAPTER I: The Myth of “Will Provide You with What You Need to Survive…”

The Earthship greenhouse is not just designed to provide a space to collect natural heat and light from the sun. It is also intended to be used as a greenhouse for growing your own food. The plants in the greenhouse are fed by a greywater system that uses reclaimed shower and sink water to water the plants, which then clean the water for use in toilets later. That is a cool idea! In the Earthship literature and books, it is emphasized that that the Earthship greenhouse can grow “all the food you need to survive.”

Of the people whose Earthships we surveyed, who we interviewed, who commented on blogs or forums, or who answered our surveys… none were able to corroborate this ideal. Certainly the greenhouses can provide some food. But, the people we spoke to said that they could not grow their own food in sufficient supply to say they were provided all they need. They used grocery stores, farmers markets, or CSAs as their primary source of food. The Earthship greenhouse served as a supplemental resource, and only seasonally, in many cases.

An architect who blogs anonymously was in the audience at one of the Earthship lectures in Australia. Afterwards, he reported in his blog that he struggled with the lifestyle and thermal performance data presented, as the presentations implied the information presented was an “undisputed truth” when in fact some of the data presented showed clearly that there were issues with performance. But, people would have to know what to look for in order to determine what parts were concerning. (This is why we attempt to explain the width and breadth of the research in Chapter 2.) He went on to question if the fish or water plants in the pond systems used for aquaponics were edible. He then calculated that in order to eat fish in the recommended dietary amounts of three times a week, you would need to harvest at least 12 fish each month. Clearly that would require a large and sophisticated system, which would put this ideal out of reach for the scale and budget of most Earthships.

This vision of providing all we need through maximizing the value of our space is awesome. We get it. We do. But it does not seem possible to produce enough food working at the scale of a single Earthship to meet this ideal.

According to the research completed by Kruis and Heun in 2007, a family of four living in an Earthship would require 98 gallons (370L) of water per day, or 37,500 gallons (135,000L) of water per year. They identified in their research that the water requirement was totally achievable in a wet place like Michigan, but those quantities could not be achieved in Hawaii, New Mexico, or Alaska. This corroborates our experience in Taos where most of the Earthship owners we know have to buy water. This makes a backup dependable water supply essential for many locations.