Improving efficiency of micro gas turbine systems by integration of combustor and recuperator using additive manufacturing techniques

World energy consumption is rapidly increasing, and global rising patterns show a higher consumption increase in residential and commercial buildings. Combined heat and power (CHP) systems have been developed and commercialised to distribute and decentralise electricity generation for domestic applications to reduce energy consumption and gas emissions. The use of a micro gas turbine (MGT) shows a number of advantages over other CHP systems including smaller size, ease of operation, and competitive maintenance cost. The low efficiency of the current MGT units in the market combined with the urgent requirement for highly efficient and low-emission energy conversion systems are the motivations for the development of new MGTs using additive manufacturing (AM) techniques. In this study, the current metal-AM systems are reviewed, the development of the MGT combustor and heat exchanger is presented, and the challenges and opportunities toward manufacturing more efficient MGT for domestic applications are discussed. The integration of the combustor and recuperator of the hot section of an MGT is proposed to achieve up to 5% improvement in efficiency with a significant reduction in the weight and size of the system.