In the sweltering heat of India's Thar desert, where summer highs soar above 50 degrees Celsius, an architecturally striking school is an oasis of cool thanks to a combination of age-old techniques and modern design.

The Rajkumari Ratnavati girls' school uses the same yellow sandstone as the 12th-century fort in nearby Jaisalmer, in India's western state of Rajasthan, dubbed the "golden city" due to the colour of the rock.

Like the fort, the school has thick rubble walls that help bounce back the heat, while the interior is plastered with lime, a porous material that regulates humidity and aids natural cooling.

Unlike the ancient fort, its roof is lined with solar panels, which provide all the school's power in an area with frequent electricity cuts.

Temperatures inside the school, designed by US-based architect Diana Kellogg and built by local artisans -- many of them parents of pupils -- can be as much as 20 percent lower than those outside.

"I love going to the school," said eight-year-old Khushboo Kumari, one of the 170 students.

"The air feels as if it is coming from an AC."

The school's classrooms are arranged around an open elliptical courtyard resembling a Roman coliseum, and walls with grids of vents create shade while allowing for cooling airflow.

Elevated windows allow hot air to escape as it rises. Rainwater is harvested from the flat roof.

In some places, the walls are dotted with perforations -- a technique known as "jali" that was traditionally used for modesty, shielding women from view in the conservative society.

At the school, it is used to promote ventilation, creating a breeze channelled by the building's oval shape.