Evaluation of Optimal Criteria for Designing Solar Greenhouses in Cold Climate Residential Buildings (case Study: Tabriz, Iran)

Abstract

Since a major part of energy in cold climates is spent on heating, using alternative methods to heat buildings is of particular importance for buildings. Solar greenhouses are inactive building solutions that absorb solar energy to provide heating in the side spaces. Greenhouse efficiency depends on several factors. The research carried out so far has used these factors in the design of a solar greenhouse to reduce energy consumption, which has finally been compared with the non-applied state of this system. The purpose of this study is to investigate the physical characteristics such as “depth”, “protrusion”, “roof slope”, and “orientation” of solar greenhouses and the influence of each factor in different modes and hours in the cold climate of Tabriz. For this purpose, a simulation has been made using “Energy Plus” software. In the next step, the optimal modes of solar greenhouse design are presented by comparing the different states of each physical factor on the first and the middle day of each month in a 6-hours period. Research results show; increasing the surface while the sun is shining and using more depth when there is no sun will maintain indoor temperature. Also, using two or three-way greenhouses (east and south) increases the efficiency of the greenhouse by 30%. The roof slope has no effect on heating the room adjacent to the greenhouse. Also, the absence of protrusions helps adjust the room temperature relative to the outside environment by up to 20 %. No significant effect on temperature was observed in calculating the ratio of greenhouse area to room area in summer. But in the cold season, a large greenhouse area greatly impacts by up to 15 %.