The study aims to compare V4 industry subsectors and identify the most promising for renewables cooperation, investment and development. This is based on publicly available industry data that is consistent across V4 countries, which is rather limited to energy consumption and fuel type. Therefore, subsectors are deemed consequential in terms of overall energy consumption, with special attention to solid fuels and natural gas with outsized emissions and energy security impact. The next consideration is the maturity of the applicable clean technology, between proven/bankable and developmental pilot projects.