Central Lakes College is partnering with the University of Minnesota Extension Regional Sustainable Development Partnerships and the Center for Sustainable Building Research at the University of Minnesota College of Design to test a prototype deep winter greenhouse.

The greenhouse is designed to help farmers grow fresh produce throughout the winter months. Deep winter greenhouses are passive solar, low-cost, low-carbon winter food production systems.

Producers using deep winter greenhouse technology are able to grow winter-hardy crops such as lettuces, cole crops and various sprouts with little or no added heat. The structure is built with a south-facing, angled glazing wall that captures heat from the sun.

Heat is stored in an underground rock bed and dissipates into the above-ground planting area at night. The university's prototype builds on earlier designs to increase insulation capacity and reduce electric use in the greenhouse.

"The deep winter greenhouse project is an important step in determining best practices for extending the growing season during the winter months in Minnesota while also reducing heating costs," said Jeff Dirks, CLC horticulture instructor, in a news release. "This will in turn help improve the security and sustainability of our local food supply by allowing more food production during the harshest time of the year."