Trombe walls consist of dark walls situated on the south side of houses and made of building materials. They’re usually covered with vertical glasses and have flat panels consisting of PCMs. Each flat panel can be moved to any angle to absorb heat during the day. Sunlight can go through these panels too so it can enter the house whenever it’s needed.
Sun’s heat during the day will stay in a space between the panel and the glass, and then PCMs inside the panel will absorb it and change phases from solid to liquid. At night, the temperature of the wall and the adjacent layers will go down till they reach the house’s temperature; this will cause the cold air to be denser in the glass space, cold air will go through the house from down and hot air will go through the wall chambers to the space between the wall and the glass.