Winter is coming, but that doesn't mean your farming productivity has to grind to a halt. Enter the world of Deep Winter Greenhouses (DWGs), an innovative solution designed to help you grow your favorite green, leafy, and cold-hardy crops even through the frosty months. Unlike traditional greenhouses that rely on fossil fuels and artificial heating methods to maintain the ideal temperature, DWGs are a testament to sustainable, eco-friendly, and cost-effective farming practices. You've come to the right place if you're curious about the key differences between these two types of greenhouses and how a DWG can revolutionize your winter crop production. Join us as we explore the unique features, benefits, and challenges of Deep Winter Greenhouses and how they compare to their traditional counterparts. Welcome to the new age of winter agriculture!
1. Definition of a Deep Winter Greenhouse
A Deep Winter Greenhouse (DWG) is an innovative and sustainable approach to year-round crop production in cold climates, allowing for a reduction in the use of fossil fuels typically required for
2. Use of Passive Solar Technology
Passive solar technology is a crucial aspect of deep winter greenhouses (DWG) that sets them apart from traditional greenhouses. This approach involves harnessing solar energy to heat the greenhouse, minimizing reliance on external heating sources. Here are some critical points regarding DWG's passive solar technology:
- DWGs are oriented east-west, allowing the south-facing glazing wall to be optimally angled to capture maximum solar energy on the shortest day of the year.
- The sun's heat is absorbed by the air inside the greenhouse, which is then blown underground and stored in a thermal mass made of rock or soil.
- This stored heat, acting as a "heat battery," maintains the greenhouse's temperature overnight or on colder days, reducing the need for additional heating sources.
- By maximizing solar energy, DWGs can support year-round crop production while significantly reducing energy consumption and costs.
Incorporating passive solar technology into a greenhouse design leads to impressive energy savings and contributes to a more sustainable and environmentally friendly approach to crop production. [3][4]
3. East-West Orientation and South-Facing Glazing Wall
One crucial aspect of Deep Winter Greenhouses (DWGs) that differentiates them from traditional greenhouses is their east-west orientation and the south-facing glazing wall. This strategic placement serves to:
• Maximize solar energy absorption: The south-facing glazing wall is precisely angled based on latitude, ensuring optimal solar energy capture on the shortest day of the year.
• Enhance thermal efficiency: DWGs rely on passive solar heating, using the sun's energy to warm the interior without additional heating sources.
• Promote year-round production capacity: The efficient harnessing of solar energy makes it possible to grow cold-hardy crops even in the harshest winter months in northern climates.
As highlighted by the University of Minnesota Extension, the east-west orientation and south-facing glazing wall ensure DWGs can support year-round crop production without heavily relying on fossil fuels for heating.
4. Thermal Mass Storage for Heat
One of the key components that set a Deep Winter Greenhouse (DWG) apart from traditional greenhouses is its innovative approach to thermal mass storage for heat. A DWG can maintain a stable temperature even during cold nights by effectively capturing the sun's energy during the day and storing it in a thermal mass made of rock or soil. Some essential features that contribute to the efficient use of thermal mass storage for heat in DWGs include:
- East-west orientation of the greenhouse with a south-facing glazing wall maximizes solar energy collection during winter months.
- Underground storage of heated air, which not only preserves heat but also minimizes heat loss through convection.
- Customizable thermal mass storage foundation options, allowing producers to choose the best fit for their budget and complexity preferences.
By relying on passive-solar technology, DWGs can significantly reduce the dependence on fossil fuel-based heat sources, paving the way for a more sustainable and eco-friendly approach to year-round food production.
5. Year-Round Production Capacity
One of the key advantages of Deep Winter Greenhouses (DWGs) is their year-round production capacity, which allows small-scale farmers and gardeners in cold regions to grow crops even during the harshest winter months. By relying on passive-solar energy and incorporating a glazing wall facing south, DWGs can efficiently capture and store solar energy in an insulated rock bed or underground thermal mass. This heat battery enables DWGs to maintain a suitable growing climate for cold-tolerant crops, such as lettuces, herbs, brassicas, Asian greens, and sprouts, throughout the year. This unique capability of DWGs not only supports local food production but also aids in reducing the reliance on fossil fuels for heating in traditional greenhouses.
6. Suitable Crops for Deep Winter Greenhouse
A Deep Winter Greenhouse (DWG) focuses on growing cold-hardy crops that thrive with minimal light, providing year-round production capacity even in northern climates. These crops are ideal for small-scale farmers and gardeners looking to maintain their crops throughout the colder months. Suitable crops for DWG production include:
- A variety of lettuces
- Herbs
- Brassicas (such as cabbage, broccoli, and kale)
- Asian greens (like bok choy and tatsoi)
- Sprouts
According to the University of Minnesota, these crops perform well in passive-solar greenhouses like DWGs due to their ability to grow even with reduced sunlight during winters. Emphasis on these suitable crops ensures not only productivity but also energy-efficient practices.
7. Resources for Building a Deep Winter Greenhouse
Numerous resources are available to assist individuals in constructing a Deep Winter Greenhouse (DWG). These tools provide valuable information on design, construction, and cost-effective methods:
- Minnesota-based plans: The University of Minnesota Extension Regional Sustainable Development Partnerships offer two DWG designs with detailed instructions and material options.
- Northlands Winter Greenhouse Manual: Supported by RSDP, this guidebook provides comprehensive construction specifications and production techniques best suited for northern climates.
- ATTRA National Center for Appropriate Technology: This valuable resource focuses on solar greenhouse design, offering extensive information and advice.
- Case studies: Reports examining successful DWG producers provide practical insights and lessons learned, offering valuable guidance for those considering a DWG enterprise.
- Enterprise budget templates: Tools to help estimate revenues and expenses for DWG operations are available, allowing users to better assess their projects' feasibility.
- Deep Winter Greenhouse Crop Recommendations: A list of crops proven to work well in a DWG system, providing valuable tips and guidelines.
- Expert advice on planting and layout: Recommendations for building and laying out shelving for planters in a DWG are available to help maximize production potential.
Utilizing these resources can help individuals interested in building a DWG to make informed decisions and succeed in their endeavors.
8. Viable Business Models for Deep Winter Greenhouse
Deep Winter Greenhouses (DWGs) present a unique and sustainable opportunity for small to medium-scale farmers and gardeners to cultivate crops year-round. Creating viable business models for these greenhouses focus on the following:
- Optimizing the use of solar energy, limiting the dependency on external heating sources, and reducing operational costs.
- Growing crops that thrive in low-light conditions, such as a variety of lettuces, herbs, brassicas, Asian greens, and sprouts.
- Tailoring thermal mass storage designs to accommodate different budgets and levels of complexity.
- Incorporating learnings from previous successful DWG producers, enhancing efficiency and productivity.
A study that analyzed eight deep winter producers in Minnesota in the winter of 2017-18 demonstrated the potential for DWGs to serve as viable business models. By implementing strategic planning, design, and crop selection, farmers can successfully build and manage a profitable DWG enterprise.
9. Case Studies of Successful Deep Winter Greenhouse Producers
Several case studies have demonstrated the success of Deep Winter Greenhouse (DWG) producers in various regions, particularly in Minnesota. These producers have implemented innovative DWG designs and production techniques to grow crops year-round, even in harsh winter conditions. Some key highlights from these case studies include:
- Utilization of passive solar technology for energy-efficient heating
- Successful growth of cold-tolerant crops such as lettuces, herbs, brassicas, Asian greens, and sprouts
- Incorporation of thermal mass storage solutions, such as rock or soil, to store solar heat
- Adoption of customized DWG designs, such as the Farm Scale Winter Greenhouse, to suit specific needs and budgets
- Collaboration with organizations like the University of Minnesota Extension Regional Sustainable Development Partnerships to share knowledge and resources
These case studies are valuable examples for aspiring DWG producers and showcase the potential for sustainable, year-round agriculture in cold climate regions.
10. Differences Between Deep Winter and Traditional Greenhouses
There are several key differences between a Deep Winter Greenhouse (DWG) and a traditional greenhouse:
- DWGs are designed to rely mainly on solar energy, limiting the use of fossil fuels for heating. This passive-solar approach helps to minimize energy consumption and promotes a more sustainable growing environment.
- A DWG's orientation and glazing wall are specifically chosen to maximize solar heat absorption, with the wall positioned at an optimal angle based on the latitude.
- A significant aspect of DWGs includes a thermal mass, which stores heat during the day and releases it at night, providing a stable temperature for plant growth.
- DWGs are particularly suitable for growing crops that thrive in low-light conditions, such as lettuces, herbs, brassicas, and sprouts. This differs from traditional greenhouses that rely on consistent, bright light for growing a more comprehensive range of plants.
- High-quality greenhouses are designed to provide year-round, energy-efficient produce growth at a competitive cost compared to traditional greenhouses.
In summary, the main differences between a DWG and a traditional greenhouse lie in their energy sources, structural design, and the types of crops best suited for growth. These distinctions make DWGs a more environmentally-conscious choice for winter crop production, while traditional greenhouses offer a versatile growing environment across a broader range of plant species.