Using solar greenhouses in cold climates and evaluating optimum type according to sizing, position and location: A case study

This study deals with a comparison among five common greenhouse types with regard to total solar radiation gaining rates in greenhouse using season under some assumptions. Additionally, possibility of using greenhouses in cold climate regions is investigated. We analyzed five greenhouse types and developed a script in MATLAB platform for the solar radiation availability. This model is applicable and suitable for other buildings and places on the world. Even-span, uneven-span, vinery, semicircular and elliptic types of greenhouses have been analyzed. A "k" value (ratio of length to width of greenhouse) and greenhouse azimuth angle (GAA) are described. Seven different floor area are assigned for each greenhouse type such as 50m2, 100m2, 150m2, 200m2, 250m2, 300m2 and 400m2, respectively. For each floor area, k value is assigned from 1 to 10. Each greenhouse is oriented in 90 different angles according to south facade. Seasonal total solar energy gaining rates is computed individually for all possible greenhouse types, area, k number and orientation. Then a comprehensive comparison is made to determine the optimal greenhouse. The results show that greenhouses are usable and suitable for using in cold climate regions to increase the productivity. In addition, the elliptic type is the optimum one in all analyzed types of greenhouses for Bayburt conditions for all floor areas. It is followed by uneven-span, even-span, semi-circular and vinery type of greenhouses respectively. Shape and type of the roof are main effective parameters on solar energy gaining rates of greenhouses. Elliptic greenhouse should be preferred on the band of the latitude of Bayburt, unless there is restrictive factor like sizing and terrain.