Fig. 1 is a planning sketch for a community health centre in Muscat, where summer cooling creates a large demand for electricity. The local authority is com...

(a) The panels use solar energy (sunlight). Photovoltaic panels convert energy from sunlight into electricity. [1]

(b) This tests how building design can reduce heat entering or remaining in a building, so less mechanical cooling is needed. Two valid descriptions are:

• Deep external shade screens block direct sunlight from reaching windows and walls, reducing solar heating of the building. [1]
• Hot-air vents allow warm air to escape near the roof. As hot air rises, the vents remove it and help keep indoor spaces cooler. [1]

The planted courtyard providing shade, and roof panels shading part of the roof, are also acceptable features. Any two well-described features gain the two marks.

(c) Energy-saving design reduces the amount of electricity the centre needs, while renewable energy supplies some electricity with a lower environmental impact. A complete explanation can include four linked points:

1. Screens, courtyard shade and ventilation reduce heat gain and allow hot air to leave, so less electricity is needed for cooling. [1]
2. The photovoltaic panels generate electricity from sunlight without burning fossil fuels. [1]
3. Sunshine is strongest during the hottest part of the day, when demand for cooling is greatest, so solar generation is particularly well matched to the centre's electricity demand. [1]
4. Using less fossil-fuel electricity reduces carbon dioxide emissions, helping make the urban development more sustainable. [1]

Further valid benefits include lower operating costs over time, improved energy security in a growing city, and demonstrating sustainable development in a public building. The key distinction is that saving energy reduces demand, whereas solar panels provide a renewable supply: combining both has a greater effect than using either one alone.