The design-specific qualities of a solar greenhouse can help you grow the food you want year round with less energy.
A Solar Greenhouse uses the sun for heat and light so you can grow plants to their highest potential. But knowing how to use one to reap all of its benefits is important.
There are 7 basic steps you need to follow to maximize the sun’s heat and light for your year round greenhouse.
Source: Mother Earth News
Your light-capturing materials should face where light and heat is coming from. In the Northern hemisphere this is the South. Since very little light comes in directly from the North, this section will serve you better if it is insulated.
2. Insulate All Other Sides
A solar greenhouse is all about capturing enough solar energy and trapping it in order to keep the greenhouse warm enough during the colder months. This will help you keep growing your Organic Plants year round.
This is usually where traditional greenhouses fail: they collect just as much energy as solar greenhouses (and often way too much) but can’t retain that heat when temperatures drop. Solar greenhouse design depends on adding insulation on every surface that is not needed for light collection.
This means the entire North wall should be fully insulated. In addition, you can / should insulate some of the east and west sidewalls. These only get direct sun for a few hours a day and thus can lose more heat than they gain, depending on your location and climate.
3. Don’t Forget to Insulate Underground
Most people think of a greenhouse as four walls and a roof, but they miss a very critical fifth plane: the ground. Just as the greenhouse will lose heat to the outside air when it’s cold, it will also lose heat to the ground below it. The topsoil freezes just like the air, and without an insulative barrier, those freezing temps will enter the greenhouse through the floor.
Moreover, by insulating around the perimeter of the greenhouse, you not only prevent heat loss through the floor, but you also couple the greenhouse to a large store of thermal mass underground.
Like other materials – water, concrete, and stone – soil acts as thermal mass, storing energy and slowly releasing it, like a battery. Connecting the greenhouse to this insulated mass helps naturally even out temperature swings.
There are a few different methods for insulating underground. The jist is to install insulation around the perimeter of the greenhouse to create a pocket of insulated soil underneath. This pocked is connected to the soil deep underground, which maintains a steady temperature year-round (often between 40-60 F in most US climates).
By insulating around the perimeter, your greenhouse has just tapped into this source of steady year-round temperatures and large store of thermal mass. This is also the reason why some people partially bury their greenhouse underground. See more on underground, or earth-sheltered greenhouses here.
4. Maximize Light and Heat in Colder Months
The angle of the sun has much to do with maximizing light and warmth. In winter, light comes in at a lower angle than in the summer months when it is much higher. You will need to angle your material, such as glass, to absorb as much of the light coming in from the South as possible. In addition, thermal mass heating will help you store the heat from the sun.
- Get Our SPECIAL EDITION Gardening Offer Here Now!
- Ditch the Bug Spray, Do THIS Instead
- Can You Get Your Next Garden For Free?
- Have Some Old Celery in Your Fridge? Here’s Something Genius You Can Do With It
- Get Our SPECIAL [LIMITED EDITION] Gardening MUG While Supplies Last