How to Build a Self-Sustaining Greenhouse
Greenhouse construction and operations can become expensive. Using the latest technology involves generators, fans, vents and other temperature and humidity controls. Inexpensive self-sustaining greenhouses can be constructed using materials that curb fluctuations in temperature and are environmentally friendly. These types of greenhouses can be customized to fit a chosen location.
Locate the greenhouse in a southwest or western position to existing structures. Set the greenhouse so it has a southeast orientation. This provides the most direct sunlight throughout the year, while reducing fluctuations in temperature and winds.
Plant deciduous trees, such as maple or oak trees, around the greenhouse. These provide shade during periods of extreme heat and prevent the greenhouse from overheating.
Dig pits out of hillsides or in the ground to create earthen walls on three sides of your greenhouse. These walls help generate a constant temperature inside the greenhouse.
Dig a 12-inch deep trench around the exterior walls of the greenhouse. Install plastic ground cover along the base of the trench. Install gravel over the plastic to the top of the soil. This prevents weeds and unwanted pests from establishing themselves close to the greenhouse.
Build a stoop at the doorway for easy access. If you build the greenhouse out of a pit, the stoop will be inside the door; put the stoop outside the door if you dig the greenhouse walls out of a hillside.
Build the entrance wall using stacked tires filled with dirt. Stack the tires in a staggered formation. Pack dirt between and in the tires. The tires act not only as a wall, but as a heat sink, collecting and releasing heat slowly into the greenhouse.
Use an old storm door for the doorway to the greenhouse entrance.
Dig a post hole at each corner of the greenhouse, deep enough to pass the frost line of the ground in your area. Cover the bottom of the hole with gravel. Slide a post into the hole. Pour concrete into the hole to set the post firmly.
Build a frame with the 2-by-4-inch boards that matches the length and width you have chosen for the walls. Attach the truss frames to the 2-by-4-inch boards. Nail the entire roof frame to the posts.
Screen any vents, fans or windows to prevent insects and weed seeds from entering the greenhouse. Keep all joints and seams tight to reduce airflow into the structure.
Lay clear plastic or coated glass over the roof. Attach the covering to the roof. Use staples to attach plastic. Use clips to attach the glass to the roof.
Lay metal pipes over the dirt floor. Run the pipes from an outside water source to the greenhouse. Run the pipes back to the water source.
Heat the water at the source; the metal pipes retain the heat of the water as it travels to the greenhouse. The metal pipes transfer the heat from the water into the floor, producing radiant heat through it. The cold water then travels back to the heating source in a cycle. The cycle repeats when the water reaches the heat source.
Install a concrete slab, brick or stone floor over the pipes. The concrete, brick and stone act as heat sinks holding heat released into it. As the heat from the pipes is released, it transfers into the concrete, brick or stone. The heat then transfers slowly from the floor into the greenhouse.
Construct a chest to hold the battery pack. Make sure you add a lock to the lid to avoid damage to the power supply.
Line up the batteries inside the chest. You need two rows of batteries.
Mount the solar panels parallel to each other. Wire the panels in parallel so that a continuous flow of power is generated from one end through the other.
Connect the leads from the exterior panels to the controller. Connect the controller to the positive terminal of the first battery in the back row with the cables.
Connect the batteries in order. Connect the batteries in parallel to create more storage capacity; this is connecting positive to positive and negative to negative. Connect the batteries in series to increase the voltage. This is connecting positive to negative. You should have two banks of batteries connected parallel, and then the banks should be connected via each battery in the back row connected to a battery in the front row.
Run another cable from the last battery (on the first row) back up to the panels. Make sure it is the negative terminal of this battery.
- Wood trusses
- Concrete blocks
- Lumber, 2-by-4-inch
- Posts, 4-by-4-inch (4)
- Drill bits
- Roll of clear plastic tarp
- Glazed glass
- Plastic ground cover
- Solar panels
- Camper or automobile batteries
- Power converter/controller
- Battery cables