Design of multi-functional solar greenhouses in high latitude areas

Abstract：There were some design and building drawbacks of traditional solar greenhouses in high latitudes areas, such assmaller front-roof angle and poor heat storage and insulation, which decreased the indoor temperature of greenhouse andrestricted vegetable growing in winter. Local planters had to supplement heat to increase vegetable yield and quality in winter,which added production cost. In addtion, because of the unreasonable spatial layout of traditional solar greenhouses andplantation planning and design, vegetable cultivation and processing links separated, and freezing damage occurred frequentlyin the course of transportation, which also restricted production of greenhouse. Based on the advantages and existing problemsof traditional solar greenhouse, and combined with the climatic characteristics of high latitudes, this paper put forward a newdesign scheme of solar greenhouse from two aspects of greenhouse structure optimization and function innovation. Using theclassical greenhouse design theory, combined with the vegetable production practice, the paper optimized the designs ofgreenhouse from lighting angle, front-roof radian, heat insulation, and calculated the snow load, wind load, moving andconstruction load and crop hanging load of the new-type solar greenhouse. Furtherly, the paper analyzed the load combinedfactor and determined key load combinations. Finally, the paper calculated the structural stability of each parameter of thegreenhouse using structural analysis software Midas. According to the stability calculation results andrelevant standards and norms in this industry, the rationality of design parameters were analyzed. The main design parameterswere that the total span is 16 m, the span of the first floor planting part is 9 m, the span of production and processing part is 7m, the total height is 6.5 m, the main lighting angle of the front-roof is 37°, and land utilization radio attains 1.7. The new-typesolar greenhouse not only makes further use of solar energy, but also has good heat insulation performance. The designrealizes that the greenhouse in high latitudes can grow fruits and vegetables without heating in winter. Based on the innovativeuse of traditional greenhouse shade part of the back wall, the new-type solar greenhouse has three-layer space fromaboveground to underground, i. e. storage space, production and processing space and potting space. The design improvedsignificantly the land utilization and realized multiple functions, such as planting, processing, storage. The new-type solargreenhouse is an innovative exploration in high latitudes, which can serve as an important role in greenhouse vegetablesplantation.