The bioshelter I helped build for my internship this summer…
I helped build a bioshelter at Froggy Pond Farm in Greenfield, Ma. I was very fortunate to work under the guidance of both Keith Zaltzberg and Sebastian (Bas) Gutwein with the Regenerative Design Group. This was an extremely interesting learning process, because I was able to use the knowledge that I immediately learned this spring from my permaculture design class at GCC, and put it to practical use.
What is a “Bioshelter” you ask? A bioshelter is like a very intensive greenhouse that has many different functions to keep the temperature inside even hotter than an average greenhouse. This is especially more beneficial for the cold winter months. A bioshelter is able accomplish these feats because of it’s many interesting and thoughtful design factors.
To start off, the bioshelter at Froggy Pond Farm was built from lumber that was hewn on the property, and then milled on site. The exterior was designed using the board and batten technique which will help the structure expand and contract between the hot and cold months. The bioshelter is divided into two main rooms. The Large room (below)
is the main south facing room that will house all of the living plants and fish. Unlike old school greenhouses, the bioshelter’s north facing wall is completely covered, so that it looses less heat in the winter. The second room behind this wall is going to house chickens! But I’m getting off track here, let’s next talk about how the bioshelter is designed to stay warm in the winter.
The bioshelter is designed to keep heat in, and also generate its own sources of heat. It does this in two ways, by relying on passive solar and biothermal heating. The passive solar comes in through the south facing glazed roof, where the sun light is intensified. It is always much warmer inside the bioshelter than outside. Next is one of the key factors of the bioshelter, the sunlight enters and warms up the two large 225 gallon water containers. These water containers, and the 150 gallon pond below them, absorb all of the suns energy during the day, and that heat is stored inside the water. As day turns to night and the inside gets colder, the water slowly dissipates heat though out the night, and this in turn keeps the bioshelter warm. This design is especially helpful in the colder winter months.
The bioshelter also generates it’s own biothermal heat. There is a compost pile under the floor boards inside by the south facing raised bed. As organic matter decomposes, it gives off heat. The compost pile was designed on the other side away from the the water tanks, to help balance out the heat distribution.
But wait, there’s more! There is a “thermal battery” designed within the bioshelter. As heat rises inside the structure, the heat will be sucked up through a vented pipe powered by a small fan. Hot air will then be transferred through the pipe and into the gravel floor of the bioshelter. This too will help keep the structure warmer through the cold winter months.
And finally, back to the chickens. The idea of housing chickens in a bioshelter is also one of generating heat (as well as providing eggs!). As the chickens run around, they emit body heat. This might seem like very little heat, but the more chickens you have, the more it adds up. Raising the temp of the bioshelter even 1 degree can be extremely beneficial when it is below freezing outside. Plus, the bioshelter will make a lovely home for chickens during the winter.
Nancee Bershoff, the owner of Froggy Pond Farm, was inspired when she payed a visit to Eric Toensmeier’s bioshelter in Holyoke, Ma. Nancee witnessed Eric growing avocados in Western Massachusetts, and Nancee said to herself, “I want to do this too!” I am very proud to have helped Nancee this summer in her dream of growing avocados in Massachusetts, and one day that will be my dream too!