To limit the global temperature increase to 1.5 °C, fossil-free energy systems will be required eventually. To understand how such systems can be designed, the current state-of-the-art is to apply techno-economical optimisation modelling with high spatial and temporal resolution. This approach relies on a number of climatic, technical and economic predictions that reach multiple decades into the future. In this paper, we investigate how the design of a fossil-free energy system for Europe is affected by changes in these assumptions. In particular, the synergy among renewable generators, power-to-heat converters, storage units, synthetic gas and transmission manage to deliver an affordable net-zero emissions system. We find that levelised cost of energy decreases due to heat savings, but not for global temperature increases. In both cases, heat pumps become less favourable as surplus electricity is more abundant for heating. Demand-side management through buildings’ thermal inertia could shape the heating demand, yet has modest impact on the system configuration. Cost reductions of heat pumps impact resistive heaters substantially, but not the opposite. Cheaper power-to-gas could lower the need for thermal energy storage.

为了将全球温度升高限制在1.5°C，最终将需要无化石能源系统。为了了解如何设计此类系统，当前的最新技术是应用具有高时空分辨率的技术经济优化模型。这种方法依赖于数十年后的许多气候，技术和经济预测。在本文中，我们调查了这些假设的变化如何影响欧洲无化石能源系统的设计。特别是，可再生发电机，电热转换器，存储单元，合成气和输电之间的协同作用设法提供了负担得起的净零排放系统。我们发现，由于节省了热量，因此平准化的能源成本下降了，但全球温度却没有上升。在这两种情况下 随着多余的电能用于加热，热泵变得越来越不利。通过建筑物的热惯性进行需求侧管理可以影响供热需求，但对系统配置的影响不大。热泵成本的降低在很大程度上影响了电阻式加热器，但并非相反。便宜的天然气发电可以降低对热能存储的需求。