How IIT Madras Built India’s First Solar Air-Conditioner 50 Years Ago

Long before sustainable cooling solutions became a global priority, Chennai had already made headlines for pioneering innovation in this space. At a time when air conditioning was a luxury and climate change was not yet a household term, a team from the Indian Institute of Technology Madras quietly made history.
Battling scorching summer temperatures and high humidity levels typical of Tamil Nadu’s capital, these researchers envisioned a future where the sun -not electricity - would power air conditioners.

According to The Hindu, in a feature titled From the Archives, the English daily republished a news report from its archives dated exactly fifty years ago under the headline ‘IIT develops solar air-conditioner’. The article said, “The Indian Institute of Technology Madras has recently developed a system of solar air-conditioning, using the ‘absorption principle,’ suitable for the hot and humid climate of India.”

“The heart of the system is the regenerator which regenerates the chemical solution used for dehumidifying the air. It uses sun’s energy directly and so no blowers or other mechanical contrivances are necessary, except a small pump to circulate the solution. The collector-cum regenerator, developed at the institute, is claimed to be more efficient than its counterparts developed in other countries.”

Describing the prototype, the article noted, “It is made of simple construction and is made of galvanized iron sheets, glass sheets, and wooden plans and the air flows through the collector by natural wind forces.” - TWL Bureau