At the Oak Ridge National Laboratory, Prof. Gao's team carried out research to develop a new high-efficiency micro-cogeneration system powered by an opposed-piston engine. This type of engine facilitates the production and assembly of the system and ensures better efficiency. Studies have shown that the system can achieve more than 35% electrical efficiency and more than 93% of the overall efficiency of a micro-cogeneration plant. According to Prof. Gao, this model will facilitate the entry of micro-cogeneration into the American residential sector.