He studied Physics and Architecture in the UK. He holds a Graduate Diploma in Architecture and Energy Studies (AA Dip. Grad) from the Architectural Association of London and a Master’s degree from the Said Business School of the University of Oxford, on “Strategy and Innovation”. Costis has carried out numerous studies and projects in Renewable Energy Sources in developing countries. He focused on solar energy applications for buildings including solar water heating and solar passive heating and cooling. He has also worked as a strategy advisor focusing on energy markets operation, energy security and energy infrastructure for large multinational companies, international organizations and governments. He has published a number of books, conference proceedings, research papers and studies on energy policy, solar energy, RES and energy markets. He is the editor of "S.E. Europe Energy Outlook (2011, 2017, 2022, 2025)", which is considered a key reference for energy in SE Europe. Since 2001, C.Stambolis has supervised and edited on a daily basis Greece’s first energy portal, www.energia.gr. He is a Fellow of the Energy Institute in London and a Founding Partner of the Energy Institute of South East Europe (IENE). Since 2018, he has been a permanent member of the Greek government’s standing committee on Energy and Climate Change (NECP).