Solar energy is available in abundance. With increasing awareness, many new buildings are designed to use most sunlight so that they can meet the energy requirements. This natural resource is now being used as passive solar heating and daylighting.
Heating: The concepts of south-facing buildings are in progress and many are on construction phases. One reason is that these buildings receive the most sunlight. Therefore, they have large south-facing windows that store the utmost sunlight. These buildings use materials that can store and absorb the sun’s heat. The sunlit floors and walls have characteristics to heat up fast and release heat at a slow rate at night. This type of passive solar design feature is known as direct gain.
Another kind of passive solar heating design feature involves the sunspaces and Trombe walls. The sunspace works on the phenomena of the greenhouse effects. It is built on the south-facing buildings, which receive the most sunlight. When sunlight strikes on glasses or other glazing surfaces, the sunspace starts warming up. The well-equipped ventilation helps to circulate heat in the entire building.
The Trombe wall is made up of materials that absorb most of the sun’s heat. It is a very thick, black painted wall, which can stock up plenty of heat during the day. To hold the heat, the pane of glass or plastic glazing is installed in front of the walls. As soon as the structure cools during the night, it releases heat inside the building.
Daylighting: This system can light up the building’s interior especially north-facing rooms and upper levels.
One limitation is that solar heating and daylighting turn into a problem during summer. However, some designs help to keep passive solar buildings cool in the summer. For example, windows can be covered by overhangs during the hot summer to prevent overheating of the buildings. To cut excess heating, the sunspaces can be removed from the building. The building can be remodelled to use fresh-air ventilation in the summer.