Global energy demand is set to increase by up to 41 percent by 2035, primarily due to rising demand in emerging countries like China and India, according to a study by BP Energy Outlook. Chillers and air conditioners make up a large proportion of this total energy consumption, say the researchers. In Germany, for example, they account for around 15 percent of total end-use electricity consumption.

In response, governments are making efforts to promote the procurement of energy-saving chillers. Adsorption chillers offer a solution that can help improve energy efficiency, and German companies like InvenSor GmbH are pushing this trend. InvenSor chillers are powered by waste heat rather than electricity and use pure water as a refrigerant.

Because of demand, InvenSor reports that it has received more orders in the past six months than in the entire business year 2013. While the chillers are being used in applications such as data centers, medical facilities and communal buildings like government offices, a growing market segment is industrial applications such as food production, plastics processing or electroplating. The company has recorded its highest recent growth rates in these areas.

 Installations of adsorption chillers powered by solar energy are increasing in warmer climates. Also, in Germany, most chillers are used in tri-generation installations, says InvenSor. These systems provide electricity, heating and cooling through a combination of combined heat and power units (CHP) and adsorption chillers. The CHP units produce electricity and waste heat that can be used directly for heating applications or for the chiller.