He is an energy economist and expert in wind and solar power, power market modeling, and electricity market design. Previously, Lion spent five years with the Swedish utility Vattenfall, where he was concerned with long-term price projections. His most recent projects were a model-based assessment of system-friendly wind power for the International Energy Agency, the construction of an open data platform for the German government, and wholesale power price modeling for the Swedish electricity trade association. He also consults the German government on wholesale and balancing market design. He has developed and maintains the open-source power market model EMMA. Lion holds a Ph.D. in energy economics, a Diploma in economics, and a Magister in political science.