The implementation of intelligent engineering infrastructure in cities necessitates the involvement of a large number of various innovative organizations. The experience of pioneer smart cities and global companies that are developing smart technologies shows that the key role in that process is played by technology entrepreneurs, i.e., a community of innovators who are capable of rapidly creating breakthrough solutions, launching them into the market, adopting and commercializing them. This study analyzes the theoretical features and current essential tasks of tech entrepreneurship as a business phenomenon and ways and means for technology entrepreneurship by corporations and independent start-ups. Exploring the case of the energy sector in smart cities which presents a growing market for technology solutions, the authors reveal the structure of the main segments of technology entrepreneurship, including electric vehicles and charging infrastructure, smart metering, telemetering, demand side management, distributed generation and micro-grids. Examples are described of tech entrepreneurship projects that were implemented by energy and telecom companies with the purpose of making urban energy smarter and more sustainable.