SHENDE LLC — Department of Agriculture SBIR Phase I: 8.12

Description

Energy-Efficient Extreme Winter Solar Greenhouse for Urban Farms in Rapid City SDProject SummaryThis collaborative proposal from Shende LLC in partnership with the researchers from theSouth Dakota School of Mines and Technology (SDSMT) Rapid City SD seeks to develop anEnergy Efficient Extreme Winter Solar Greenhouse product.Rapid City (RC) was declared as one of the cities with the most unpredictable weather.The extant winter greenhouses (GH) perform poorly in the frequent high wind hailstorms and coldwinters. RC urban farmers have limited crop choices and a short 6-7-month crop growing period.To meet consumer demand most produce is imported year round from warmer states leading tohigher produce prices and often inferior produce quality. Therefore there is an urgent need toinnovate GH structures for superior performance and durability for northern locations withextreme and unpredictable weather.We propose to investigate the applicability of a compound parabolic concentrator and oilheat transfer fluid system to convert solar energy to thermal energy. A heat exchanger systemlocated inside the highly insulated greenhouse will transfer the thermal energy to water which willbe circulated through the water lines placed in a rock bed. The circulating warm water willo o sufficiently raise the soil temperature (nighttime temperature>50 F; daytime temperature >75 F)to permit cultivation of warm weather crops all year around. Additionally the proposed designmodeled after the Chinese Solar Greenhouses will enhance the structural integrity to providesuperior high wind and hail-resilience. Techno-economic analysis using a discounted cash flowrate of return (DCFROR) model will estimate financial performance and economic feasibility.Considering the unpredictable weather of RC the researchers believe that a laboratory- scale prototype is required to gather real-time data to accurately evaluate the performanceefficiency of the GH. Synthetic data might not adequately capture the unexpected outcomes of afrequent hailstorm or adverse weather conditions typical to RC.Lack of affordable energy efficient greenhouses for unpredictable and extreme weathercoupled with the strong desire amongst the RC farmers to grow vegetables all year round are thepotential key market drivers for this product. Farmers of RC are highly interested in takingadvantage of the high demand for fresh vegetables and fruits to supplement their income.Therefore Shende LLC is confident of a strong market for their Energy-Efficient Extreme WinterSolar Greenhouse product in South Dakota and neighboring states.