Petr Holub has been promoting sustainable energy systems all his professional life. For eleven years he was Director of Chance for Buildings, a professional association of energy-saving construction, which he built into a respected organisation from its foundation in 2010. Before, he spent three years working at the Ministry of the Environment as an advisor for Ministers and Head of Sustainable Energy and Transport Department. He also worked in Hnutí Duha for many years. As a consultant, he evaluated projects financed from EEA and Norway Grants and assisted cities in their involvement in the Pact of Mayors for SEVEn.
Outside the Czech context, he is frequently seen in Brussels, where he helps set European legislation and economic instruments. He co-founded the Central and Eastern European Energy Efficiency Forum (C4E Forum), and he established the Roenef business association in Romania. As a consultant for the European Commission, he designed the settings for the energy-saving framework for Ukraine. He founded the consulting company Budovy21 in July 2021.