Rotmann was born and raised in Austria. When she was 20, she moved to Australia and studied marine biology at James Cook University, Queensland.[3] Her PhD thesis was in marine ecology and environmental studies, and focused on human-induced environmental impacts on coral reefs, including field research in Papua New Guinea.[4]
Since 2005, Rotmann has focused on sustainability implementation in policy, practice, and research. In 2011 she started her own consultancy called SEA – Sustainable Energy Advice Ltd, focusing on turning behaviour change theory into best practice.[5] From 2012 to 2018, she ran the first global research collaboration on behaviour change in demand-side management (DSM) for the International Energy Agency's Demand-Side Management Programme (now Users TCP). Her current Users TCP by IEA research project is on hard-to-reach energy users in the residential and commercial sectors.[5]
Rotmann is active in environmental advocacy. She co-chairs a group of Wellington residents opposed to the extension of Wellington International Airport's runway, and was involved with the local chapter of the Aotearoa New Zealand Extinction Rebellion group.[3] In 2011 she stood for election as the Green Party of Aotearoa New Zealand candidate for the Wairarapa electorate.[6] In 2014 she stood for Parliament again, also for the Green Party.[7]
