Cooling with Waste Heat from Compressed Air Systems – Generating Huge Energy Savings

Almost all industrial manufacturing facilities use compressed air systems. At the same time, the cooling demand in industrial facilities keeps on rising, and drives energy consumption. Adsorption cooling provides an ideal approach for solving both ends of the problem: Re-using waste heat to generate cold, thereby decreasing energy demand.

More than three quarters of the electrical energy for compressed air systems can be recovered as heat in the form of hot water. While most of the time, there is no commensurate heating demand, the temperatures are well within the sweet spot of the operation range of adsorption chillers. Therefore, combining air compressors and adsorption chillers creates the perfect opportunity for energy efficiency optimization whenever cooling is needed – whether for process cooling or for air conditioning.

Furthermore, a free cooling function (integrated as standard option in Fahrenheit adsorption chillers) allows for the cooling load to be covered in cold winter days without the need for the heat recovered from the compressed air system, which in turn can be used at that time for heating purposes – which drastically decreases the annual energy demand.

In addition, Fahrenheit adsorption chillers are also eligible for government subsidies in Germany which cover up to 40% of the capital investment costs and which significantly improve the economic viability of such applications, with payback periods ranging from 2 to 4 years.

A case example: Galek & Kowald GmbH from Mühlhausen (Thür.)/Germany planned and installed just such a system for Alupress GmbH in Hildburghausen. An eCoo 20X adsorption chiller by Fahrenheit is driven by the waste heat from air compressors. A large share of the cooling power generated by the eCoo 20X is used for drying the compressed air for the production process, covering a cooling load of 41 kW throughout the year. The eCoo 20X will save more than 60 MWh_e per year, paying back the investment in less than 3 years.