This is an April 2016 Blog Post on how we built a Thermal Mass Rocket Stove at Jordan Rubin’s ‘Heal the Planet Farm’.
(We cover the foundations of rocket stove building at every Permaculture Design Certificate (PDC) course we host.)Schedule of Upcoming Courses
We call it the Epic Greenhouse Rocket-Mass Heater because of it’s sheer size and multiple modifications we designed into it. The whole stove is built around an 8″ flue system that exits outside of the greenhouse below floor level, under the greenhouse end-wall, and then turns towards the sky.
Designed by Bill Wilson (MWP) and Kevin Kepplinger (HTP Farm) Construction and Design Assistance from Heal the Planet Farm Team (All are Midwest Permaculture PDC graduates)
The key modifications we made to this stove that are not usually found on more traditional rocket mass heaters are:
The feed chamber is very large capable of holding full-sized firewood logs so it can be loaded to burn for up to 4 hours at a time and produce a lot of heat.
The thermal battery or thermal mass is below grade and insulated so the heat will not wick into the soil surrounding it but instead radiate up to keep fish (aquaponics system) and bedding plants warm even in the dead of winter.
We installed a multiple-speed flue fan and a flue damper near the end of the exhaust pipe to give ourselves greater control over the speed of the exhaust and even the burn. We can slow the exhaust down to hold the heat in the thermal mass longer when it’s hot or speed it up when we need a stronger pull to get it started. We know this is unorthodox and a bit like cheating, but it’s very helpful and the fan is variable speed using very little electricity.
Why Season Extenders are part of This Permaculture Design
For those of us who garden in a temperate climate (freezes in winter), we know only too well the disappointment when, for example, our indeterminate tomato plants are full of tomatoes in the fall, they are producing wonderfully, and then the first frost hits. The tomato season is now over and the plants were producing so well for the last 4 weeks.
Now, suppose we created a very simple cold frame or low tunnel to start our tomato plants earlier in the spring so that they had a 4-week earlier start. That would mean that we would now get 8 weeks of tomatoes by the time the fall frost came calling. We just doubled our production from 4 to 8 weeks with a little protection in the spring.
But what if we constructed some kind of added protection in the fall as well, before the frost hit, and ended up getting yet another 4 weeks of production? We just tripled our yield with a little help from our season extenders.
Our Objective: To include in this permaculture design a variety of hoop-houses, cold-frames and other frost/wind protection techniques with the goal of increasing our yields while minimizing the work typically required to get those yields. This is a primary permaculture design principle.
Season Extenders Explained
Here is an introduction to various options–some traditional, some creative.
I am very much looking forward to teaching this upcoming PDC with fellow permaculture designers/farmers, Josh and Brian Shultz. Both are Midwest Permaculture PDC Graduates but had been doing advanced permaculture work long before that.
While there, we will learn about the work they are doing on behalf of the environment and how they are teaching ‘care of earth’ to school students and the general public. The people at PCCI are walking the talk every day. We will be in great hands and at a great location for this training.
And when it is time to get out of the classroom and learn by doing and seeing I will be taking everyone over to Josh and Brian’s combined endeavors, Fair Lake Farm and Cedar Creek Permaculture Farm (see picture summary below). They have both done amazing work in various fields and I know that as students, you will be learning a great deal by examining what they have accomplished and are planning to do.
To be clear, since this will be a PDC course I will be teaching the full PDC Curriculum including urban, suburban and residential permaculture applications. We will be looking at how to design for various climates and for unusual circumstances.
Students will also be invited to bring their own design projects for we will set aside an entire evening to do nothing but explore the real-life design challenges of those who have a specific project. Not everyone will or is expected to bring a project but we will all learn by exploring those projects that are brought to the table. This is going to be a fabulous training and I am looking forward to meeting many new permaculture minds and hearts.
Permaculture Greenhouse A Friend of ours has been working on this greenhouse design for several years. We wanted to share it with others visiting our website. What do you think? Is this a ‘Permaculture’ greenhouse?
Why A Year-Round Greenhouse is part of This Permaculture Design
It doesn’t take much for those of us in temperate climate zones to imagine the allure for year-round greenhouses. Fresh tomatoes in January are compelling! A more controlled and protected environment in spring, summer and fall has real advantages as well. And from a small business perspective, what if we could produce enough fresh produce for ourselves and a handful of our neighbors 52 weeks of the year?
In a good permaculture design for an urban residence, a homestead or a farm, the first thing we seek to accomplish is the efficient storage of summer crops through root cellaring, drying, fermentation and other forms of preserving. But once we accomplish this… few things beat fresh produce in the middle of winter.
To get this done we need to design for the two major demands of plants that are in short supply during the winter months: heat and light.
Originally constructed as an industrial sized greenhouse, this structure has been exposed and empty for the last 30 years. Located in the CSC apple orchard, it had been a popular roosting site for our orchard turkeys. Unfortunately for them we were determined to get some use out of the Buckminster Fuller inspired geodesic frame.