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Deep Winter Greenhouses

What is a deep winter greenhouse?

Farm scale deep winter greenhouse, 2023. Credit: Daniel Handeen, UMN College of Design, Center for Sustainable Building Research

Deep winter greenhouses (DWG) are passive-solar greenhouses that utilize the energy from the sun as the primary source of heat.

A deep winter greenhouse in production.

DWGs are built in an east-west position, with a south-facing glazing wall that is steeply sloped to capture the most possible solar energy on the coldest days of the year. The solar-heated air inside is drawn underground with a fan and stored in an insulated thermal mass of soil or rock where it is available to heat the space at night.

The University of Minnesota Extension, College of Design, CFANS, and Mechanical Engineering are partnering with five farmer partners throughout Greater Minnesota to build and test prototype farm scale deep winter greenhouses:

These farms will build the farm scale deep winter greenhouse prototype, grow winter crops, and work with the UMN on conducting research trials, outreach events, and winter production workshops. 

Upcoming events

Farm Scale Winter Greenhouse 2.1 prototype

DWGs in Minnesota can be used to grow cold-hardy crops that thrive with minimal light, providing year-round production capacity for small-scale farmers and gardeners. Crops well-suited to DWG production include a variety of lettuces, herbs, brassicas, Asian greens, and sprouts.

Request building documents

Resources

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Stories from Extension

RDSP citizen board members Bob Backman and Doug Franchot at IonE sustainability symposium

Focused on sustainability and driven by research with rural communities, RSDP and IonE are working together to help Minnesotans and the environment prosper.

Greens growing in a farm-scale deep winter greenhouse.

Farm-scale deep winter greenhouses are showing great promise for energy efficient winter food production. Farmers and researchers have an exciting opportunity to partner to grow this technology across Minnesota.

Kite and wind turbine with a bright blue sky

In honor of Earth Day 2022, Statewide Director Kathy Draeger shared thoughts on RSDP’s work related to climate change.

The farm scale deep winter greenhouse initiative is supported by the Minnesota Department of Agriculture.

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