Demonstration of Root Zone Heating Supported by the Developed Biomass Greenhouse Heating System

View the project final report

Commodities

Practices

• Crop Production: greenhouses
• Energy: energy conservation/efficiency

There has been high demand for local food in western North Carolina. Food surveys in the mountain region of NC and TN conducted by the Appalachian Sustainable Agriculture Project (ASAP) discovered that demand for local foods exceeds potential supply. The purchase of local foods supports local farmers and local economies, provides improved health benefits, and has a positive environmental impact. However, the limited availability of locally grown food along with consistency and access hinders these benefits.

There are several reasons for limited availability of locally grown food with consistency in this region. The rough mountainous terrain and frigid winter weather limit agricultural opportunities such as the size of farms, shorter growing season, and limited large-scale mechanized farming operations. In addition, dramatic weather change in mountain region increases risks in agriculture such as spring frost damage. The result is low income and high rates of off-farm workers. Therefore, most Appalachian farmers are small-scale family owned and struggle to maintain profitability with limited resources.

Some Appalachian farmers dedicate a portion of their limited acreage to greenhouse production to maintain their profitability. Greenhouse production can extend the growing season and prevent damages from dramatic weather change, but the requisite heating and energy costs exclude many producers from being able to afford a heated greenhouse.

We propose growing season extension and coping with dramatic weather change with biomass heated greenhouses as a solution for these challenges. Biomass energy, generated from all available feedstock from the farm such as livestock manure, agricultural waste, wood waste, and food waste, can be an affordable greenhouse-heating energy source for those seeking lower energy costs to extend the growing season.

We have built pilot systems at two cooperative farmers. One includes a biochar kiln, solar thermal collector and a thermal battery. The other includes a solar collector, biochar kiln and root zone heating system.

During this proposed project period, we would like to demonstrate the performance of heat exchanger in the kiln; temperature distribution on growing area with/without root zone heating system; and overall performance of the pilot systems.