Firm touts system for turning sun's heat into cool air

The stifling heat often experienced in desert regions may have resulted in soaring energy demand and carbon emissions over the past few decades as air conditioning systems have become ubiquitous in many buildings across the Middle East, Australia and Southern US. But now a Turkish company called Solitem claims it can tackle air conditioning's huge environmental footprint by harnessing the heat of the sun itself to power new zero-emission solar cooling systems capable of keeping buildings cool for much of the day.

Solitem's technology integrates parabolic trough solar panels typically used in solar thermal power plants with an absorption chiller system capable of using concentrated heat energy to cool water.

Typical absorption chillers struggle to cope with the 200 degree heat that can be produced by parabolic troughs and used to produce super-heated steam, according to Solitem managing director Dr Ahmet Lokurlu. But he insists the company has resolved the problem with the development of a double-effect absorption chiller that can operate at temperatures of between 150 and 200 degrees centigrade and use the energy to cool water to about six degrees.

"The secret lies in complex software that regulates the energy flows in the system and delivers a constant stream of water cooled to about six degrees, the perfect temperature for conventional air conditioning units," he explained.

According to Lokurlu the system can provide zero carbon cooling in daylight hours and can also hold enough energy in hot water storage tanks to continue to provide cooling for a further four to six hours after nightfall, meaning buildings only have to rely on backup power for their cooling systems for a few hours per day.

The company is now seeking to scale up its commercial operations after Germany-based engineering giant MAN Ferrostaal acquired a 20.1 per cent stake in the firm and signed an agreement to resell its technology.

Lokurlu said that MAN Ferrostaal would provide Solitem with the sales and installation resources required to target a wider range of customers. "MAN Ferrostaal is already heavily involved in conventional air conditioning systems and has the ability to install our technology on large-scale sites," he said. " The system has the potential to deliver cost and carbon savings to large properties across the Middle East, Africa, the US, Australia and the Mediterranean and this partnership gives us the ability to reach those customers."