Lighting and Energy

## Lighting

* It’s lighting produced by electrical generation. Efficient artificial lighting produces the optimum lighting level for the task while using a minimum amount of electrical energy.
* The solar lighting system uses a roof mounted solar collector to concentrate visible sunlight into a bundle of plastic optical fibers.

* Optical fibers penetrate the roof and distribute the sunlight to multiply luminaries within the building.
* Properties:

1. Sensors determine where light levels are too low, where the dark
2. As the light levels begin to change, sensors provide feedback to the lamps, which adjust levels of artificial light to maintain constant lighting in the room

* Location:

1. The host of sunlight on the roof of building or on facade.
2. Fiber optics through structure to transfer the sun light.
3. Sunlight distributor in building spaces.

## Shading

The process of controlling the sunlight entering a building
Applies in :

1. Lighting [ Shading ]
2. Cooling System

* The process of controlling the sunlight entering a building, can be accomplished through a number of methods.
* The techniques employed generally depend on the climate and the use of the space.
* Properties :

1. Well-designed sun control and shading devices can dramatically reduce building peak heat gain and cooling requirements and improve the natural lighting quality of building interiors.
2. Depending on the amount and location of fenestration, reductions in annual cooling energy consumption of 5% to 15% have been reported.
3. Sun control and shading devices can also improve user visual comfort
4. Shading devices offer the opportunity of differentiating one building facade from another.

* Types :

1. Solar screens
2. Roll-down blinds
3. Shutters
4. Vertical louvers
5. Horizontal louvers
6. Canvas awnings (fixed or movable)
7. Solar panels

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* Location :

1. Doors and windows that exposed to sun direction
2. Cars parking
3. Out door siting area

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## Solar Collectors

        \*Solar thermal collector collect heat by absorbing sunlight ( sun radiation )

* Sun radiation is energy in form of electromagnetic waves .
* The heat is transferred by circulating water, antifreeze, or sometimes air to another location for immediate use or storage for later use.
* Types :

1. Stationary : Flat plate collector (FPC) & Evacuated tube collector (ETC)
2. Sun tracking : (single axis ) or (two – axis ) .

* Location :

1. On the roof .
2. Open spaces exposed to the sun

## Wind

Wind catcher:A wind catcher is a traditional Persian architectural element to create natural ventilation in buildings. Wind catchers come in various designs: uni-directional, bi-directional, and multi-directional. Wind catchers remain present in many countries and can be found in traditional Persian-influenced architecture throughout the Middle East.
Wind catchers tend to have one, four, or eight openings. The construction of a wind catcher depends on the direction of airflow at that specific location: if the wind tends to blow from only one side, it is built with only one downwind opening.
To keep buildings free of dust and sand blown in from the desert, wind catchers were built facing away from the wind.

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