The role of energy prosumers in the transition of the Finnish energy system towards 100 % renewable energy by 2050

A cost-optimised transition pathway towards 100 % renewable energy was simulated for Finland. This transition was consistent with EU and international targets to achieve sstainability, while maintaining national competitiveness. Finland was divided into 7 regions that account for resource distribution and demand differences at high spatial and hourly time resolutions. Results indicate that levelised cost of electricity can decrease from 61 (sic)/MWh in 2015 to 53 (sic)/MWh in 2050 and that levelised cost of heat can decrease from 29 (sic)/MWh to 20 (sic)/MWh based on the assumptions used in this study. Transport sector costs decrease for most vehicle classes through electrification but increase marginally for classes that use bioenergy-based or sustainable synthetic fuels. Costs decrease through the adoption of flexible generation by several renewable energy technologies, intra-regional interconnections, and the use of low-cost energy storage solutions. Results show less need for combined heat and power plants as the electrification increases through sector integration. Individuals and groups can become prosumers of energy, motivated by a desire to contribute to climate action and making choices for lower cost, sustainable energy. Collectively, society can increase a sense of agency through lower exposure to risks. A 100 % renewable energy system can be a resilient, low cost and low risk option for the future.