Frugal innovations, i.e. affordable products and services with appropriately good quality, are getting increasingly important for securing long-term competitiveness in both, the developing world and in industry nations. Nevertheless, ensuring actual implementation of technology-driven frugal inventions remains an under-researched area. This study investigates modes and routines employed by techno-entrepreneurs from industry nations when innovating frugally. The study is based on the patent data of seven auto component sector firms from Germany with a documented history of contributing cost-effective solutions to frugal vehicles. With the help of a keyword analysis we identify the role of frugality in (patented) technical inventions. Select case studies of frugal inventions show that cost effectiveness and environmental sustainability can be often achieved by simplification of design and production process, as well as by eliminating avoidable complexity, e.g. through standardization. The study shows that frugal inventions in the investigated firms are often driven by individual inventors, while potentials of open global innovation networks are under-utilized. Furthermore, the study shows that frugality can (only) be achieved by a holistic approach that encompasses the entire value chain, including logistics and waste management. The results are potentially beneficial for techno-entrepreneurs across industry sectors and product domains.