Tomáš Pastrňák has been the director of Energon Advanced Energetics since 2017, which specializes in the design and construction of large-capacity battery energy storage systems (BESS) and complex EPC units, including photovoltaic, wind and hydropower plants. It has been active in the energy sector since 2006. In the past, he was involved in the completion of the Ledvice power plant, and for several years he led the construction of a power plant in Turkey.

He is the author of a unique concept of an "all-in-one" battery container. The company introduced the first one with a capacity of 1.3 MWh in 2018. At the time, it was only the third battery storage of this size in the country and the first to be wholly designed and assembled domestically.