John Mennel is a Strategy Partner and a leader in Deloitte’s global Sustainability practice.  For over a decade, he has been working with large companies to help decarbonize operations, make greater use of affordable clean power and bring low carbon solutions and products to market.  He is also responsible for the data, models, AI and software that Deloitte Sustainability teams use to deliver value to clients. 

In prior roles, John led Deloitte’s relationship with the Department of the Interior, led public sector transformation and competitiveness projects across the Middle East, Africa and Europe, and held senior product management positions in the technology industry.  He started his career with Deloitte in Moscow during the perestroika period.  He holds a Master of Business Administration (MBA) from the Harvard Business School and a Bachelor of Arts (BA) from Brown University.  John is an avid backpacker and spends as much time as possible in the mountains.  He completed a through hike of the Colorado Trail in 2023.