Figure 13: Daily heat balance through 1 m2 of dome during the coldest winter day versus Earth’s latitude (Northern hemisphere example). Data used for computations (see (6)–(14)): temperature inside the dome is = +20°C, outside are = −10, −30, −50°C; reflectivity coefficient of mirror is = 0.9; coefficient transparency of film is = 0.9; convectively coefficients are = = 30; thickness of film layers are = = 0.0001 m; thickness of air layer is δ = 1 m; coefficient of film heat transfer is = = 0.75, for air = 0.0244; ratio of cover blackness = = 0.9; for louvers, .