Cities are a major contributor to global pollution, and the main reason for this is the sourcing of energy from pollutant fossil fuels. The city of Vancouver has tackled its energy needs through the creation of a strategy to use 100% renewable energy by 2050, the first city in North America to do so. Vancouver's strategy focuses on the two major contributors to pollution, buildings and transportation. It aims to promote the electrification of individual transport and to electrify Vancouver's public transport. In the building sector, the city attempts to ensure renewable energy supply and retrofits existing buildings to minimise energy demands. Energy supply models and data are used to ensure maximum efficiency in the shift towards renewables.