I doubt, however, what comes to most people's mind is an underground construction, with a translucent ceiling, designed to maximize the energy from the sun in order to grow the food needed to feed one's family. That's because when we say greenhouse we think of something that is usually above ground, like most houses are. Well, I would like to introduce the reader to the Walipini, the underground greenhouse designed to maximize the sun's energy in order to produce the food needed to feed one's family. Walipini comes from the Aymara (a native people of Bolivia) language and means, "place of warmth".
I first heard about it through a friend of mine who had asked if I knew about it. I didn't, so I took the time to do some research and found a great manual on how to construct a Walipini. I found the manual on the website for the Benson Agriculture and Food Institute, a 501(c)3 organization established in the mid-70's at Brigham Young University, and named after Ezra Taft Benson who was U.S. Secretary of Agriculture for both presidential terms of Dwight D. Eisenhower. While reading through the manual I was thrilled to see simple human ingenuity paired with nature in a way that made so much sense. So why does it make sense to go underground with your food production?
Here's why:
The Earth’s center is HOT and heats the entire globe from the inside out. At bout 4 feet from the Earth's surface the heating process is noticeable as the temperature, in most places at 4 feet deep, stays between 50 and 60 degrees Fahrenheit. When the temperature above ground is cold, like 10ยบ F with a cold wind, the underground temperature 4 feet deep will be at least 50 degrees most of the time. Now, the additional heat needed by the sun is much less with the Walipini than in an above ground greenhouse, because the Earth is providing most of the heat. So with an underground temperature of 50 degrees (regardless of the above ground temperature), and a needed growing temperature of around 80 degrees, the Walipini only needs to increase the temperature by 30 degrees. An above ground temperature of 10 degrees requires heating a conventional above ground greenhouse 70 degrees for an ambient temperature of 80 degrees. That is a tremendous savings in energy year-round.
Energy savings is one reason, but the cost of construction is another. Most conventional greenhouses can be pricey, especially if you want to build something substantial that will actually be productive enough for your dietary needs, year-round. The Walipini, is rather cheep because most of the materials needed are provided by the Earth, yet if you factor in the amount of labor needed to build it, it may balance out the costs to construct. However, if you don't mind working hard to dig an enormous 6 foot hole your self, then you will notice the savings in construction.
For those who may not be ambitious enough to dig an enormous 6 foot hole, then an alternative underground food production system would be the Panqar Huyu, again from the Aymara language, meaning "flower bed". It is a semi-underground garden bed that uses the same concept as the Walipini, only you don't dig as deep or as big. A manual for how to construct a Panqar Huyu can be found at the Benson Institute as well.
The idea of taking your food production underground in order to use the Earth's temperature control system to maintain ideal growing temperature for your operation is wonderful and I would say, inspired. It would seem there is something at the root of using nature's abundant energy sources in conjunction with mankinds' abundant knowledge source, in order to be independent and self-sufficient, that has little to do with food. It would seem another human need is being fulfilled and I think it can be found in the words of Ezra Taft Benson, during the inaugural address of the Benson Institute, after humbly accepting the fact that the institute will be named after him, when he said the following:
We need – and the world needs – a strong America in the critical years ahead. Freedom is a God-given, eternal principle vouchsafed to us under the Constitution. It must be continually guarded as something more precious than life itself. It is doubtful if any man can be politically free who depends upon the state for sustenance. - Ezra Taft Benson, BYU, 1975Freedom is the principle motivating the idea of the Walipini. Freedom from hunger, freedom from disease, freedom from oppression, and freedom from enslavement. This is what any farmer of the future should consider when developing new farming practices that would sustain themselves and those around them in a cost effective and energy efficient manner. The Walipini is an example of a farming practice that would maintain food independence and food security year-round, and thus maintain freedom of the individual engaged in such a farming practice.
In order to be free, happy, and prosperous, the future will need to be a place where food systems maximize independence rather than profits. Where farming practices mimic and/or work with nature rather than alter it or work against it. Where food production and productivity is based on ideas that will perpetuate life and enhance the livability of future generations. The Walipini, being a food system and farming practice described here, is definitely not your gramma's greenhouse; it is your children's.
Sources
Benson Agriculture and Food Institute, "Walipini Construction (The Underground Greenhouse)", Brigham Young University, Provo, UT, 2002
Velasco, Noel, "Manual for the Construction and Management of Panqar Huyus (Semi-underground organic bed)", Benson Agriculture and Food Institute, Brigham Young University, Provo, UT, 2003
Benson, Ezra Taft, Benson Agriculture and Food Institute Inaugural Address, Brigham Young University, 1975
Walipini Underground Greenhouses http://peswiki.com/index.php/Directory:Walipini_Underground_Greenhouses