Masdar has recently installed solar powered absorption chillers to air condition their site offices. This is really welcome news. I had often wondered during my visits there about the prominence of the condensing units located all around the periphery of the site offices and how long this practical convenience would last before a more sustainable solution was implemented.
The story got me thinking about the potentials for absorption chiller technology and I discovered some articles and research from a couple years back about Einstein's Refrigerator. It was a collaboration between Einstein and Leo Szilard and was patented in 1930. It could be powered by solar thermal energy, is silent, and has no moving parts. Its design was intended for food storage and it could still be applicable to that for sunny regions without much access to electricity. But similar technology is being perfected for use with air conditioning.
Companies like Solem Consulting™ and Sopogy MicroCSP™ are employing these systems today and they could be cost competitive to compressor refrigerant type of chillers in the coming years. But even today, they are the obvious preferred choice for sustainable development. They can run on solar energy alone, they use non greenhouse gas liquids (ammonia), could last for a hundred years without maintenance (no moving parts on the Einstein version), and they are silent.
As a start, I'd like to see all AC bus shelters switch over to using this technology. The energy savings and CO2 emissions reductions would be enormous.
A related brief TED talk worth watching is Adam Grosser on a new vision for refrigeration.