Incorporating low grade energy recovery in process integrated systems

Low grade energy streams are available in large quantities and end up as loss in the energy consumption in the United States. For sustainability and security of the energy future, various research efforts are under way to harness this low grade energy. This paper provides a review of low grade energy resources available in industry, and applications where that can be used. Then, an underdeveloped research area is identified in the integration of the low grade energy in process systems. Some of these areas include the use of low grade solar energy or flare systems, and applications include desalination, district heating, refrigeration, etc. A few applications related to saline agriculture are also identified. This work provides a basis where the recovery of low grade energy sources and subsequent integration can provide potential cost savings, environmental benefits and social impacts. The paper also concludes that further research is needed at the systems level for including sustainability considerations in the low grade energy integration of processes.