New Technologies for Reducing and Recovering Wasted Heat Energy in Industry

According to the U.S. Department of Energy (DOE), it is estimated that up to 50% of industrial energy input is lost as waste heat in the form of exhaust gases, cooling water, heat loss from product heating. Recovering waste heat from industrial/commercial processes can be an attractive opportunity for a facility in reducing overall energy consumption. Heat recovery focuses on the utilization of a waste heat stream to do additional work elsewhere in the facility. For heat recovery to be economical, a customer facility must have a waste heat source and a simultaneous need for heating elsewhere in their facility. There are new heat pump designs such as CO2 based heat pumps, variable speed heat recovery heat pumps, and others which promise efficient heat recovery opportunities. This paper presents the results of the performance of a new variable speed heat recovery chiller that is currently being tested at Alabama Power’s Technology Applications Center (TAC) facility. Although the individual components (i.e. compressors, drives, etc) are not a new concept, the implementation and associated control of the combined system is new as it relates to heat recovery chillers and heat pumps. This is also different from heat recovery off a chiller via a desuperheater or double bundle condenser. The paper also presents a new electrotechnology application in medium-voltage called the 4kV electric boiler. This is the first electric resistance boiler of its kind in the world which was developed as a part of EPRI and Southern Company collaboration with Gaumer Process and Cleaver Brooks. Contrary to the fossil fueled boilers that have emissions and stack loss, the electric boilers are very efficient in converting the electric energy to steam and do not have stack loss. This product has a smaller footprint and also has higher energy efficiency over conventional fossil fuel fired industrial boilers. Performance characteristics and the results from the tests conducted by EPRI and Southern Company at an industrial customer site in Georgia are presented in this paper.