Net-Zero Eco-Cabins
We challenged ourselves to design off-grid cabins that function well and are comfortable throughout the year.
Cabins located in the secluded wilderness are great for resting, recovering, and enjoying nature, but servicing the site can be expensive. Our approach is to super-insulate the walls, minimize air leakage, optimize for solar gain, use a high efficiency energy recovery ventilator, heat with a high performance wood stove, and supply electricity via PV panels. The result is a cabin with a yearly heating cost equal to a face cord of wood, about a 6’ (1.2m) cube of wood.
Cabin features include:
- Modern style with large south facing triple-pane windows.
- Four options: One bedroom family style (600sf), two-bedroom (800sf), four-bedroom (1200sf), and Luxury four-bedroom (1200sf).
- Super insulation: R57.5 walls, R54 Floor, R67 roof, and R7 windows.
- Sturdy design: metal siding and metal roof
- English made Ironheart wood cook stove with overnight feed bin
- Sundanzer super-efficient refrigerator with Freezer for summer use available as an option.
- High efficiency lighting: compact florescent lighting or LED
- Solar panel photovoltaic system with battery storage and external generator hook-up.
- Oak stairs and engineered wood floors throughout
- Spacious exterior deck
The design is based on energy modeling with local weather data. This weather data includes the locations, temperature, cloud cover, wind, and precipitation. We then design and simulate a model of the cabin as if it were being used by a family. The challenge to overcome in off-grid buildings, is that studying merely the temperaure is not sufficient; the length of time, in days, that the cabin can function without sun must be considered.
The EcoCabins will have two modes: occupied and unoccupied. At the end of an occupied period, a weekend for instance, the building can be switched over to unoccupied mode. When occupied, the cabins will be heated with an Ironheart wood cook stove that has 2 burners, an oven and hot water preheat. The cabins will come with a refrigerator, hot water tank, lighting and high efficiency energy recovery ventilator.
The power supply will be sufficient to power a flat screen TV, a Blu-ray system, a stereo, laptop, coffee maker and toaster. When occupied in the summer, since Photovoltaic production is higher, a hot plate and freezer may be added to the appliance budget. When unoccupied the cabins are switched over to direct all power to heat tracing the well connection, topping up the batteries, and with the excess, powering baseboard electric heat. As an extra safeguard, the system will be programed to contact the owners should the batteries become too low, which can be supplied by an external generator (for instance via an inverter from a car).
Normal power is supplied by roof-mounted solar panels hooked up to a battery bank sized to provide sufficient power to see the cabin through 3 weeks of low sun in the winter unoccupied mode, which is the most critical demand. The Cabins should keep comfortable temperatures when left for 2 weeks, and maintain safe temperatures throughout the year.
If you want to learn more about these cabins please get in touch via Email or give us a call at 416-868-9774.
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“I went to the woods because I wished to live deliberately, to front only the essential facts of life, and see if I could not learn what it had to teach, and not, when I came to die, discover that I had not lived.” ― Henry David Thoreau, Walden