As Europe’s renewable energy capacities expand, electricity systems face increased risks of energy droughts—periods of low production coinciding with high demand. We evaluate characteristics of electricity variability due to weather variations by calculating 1,600 years of daily production and demand. Focusing on five European countries—chosen for their energy mix including hydropower—we find that energy droughts result from processes that cause (temporally) compounding impacts in the energy and meteorological system. These can turn what might have been short-term droughts into prolonged high unmet energy demand. For instance, low reservoir inflows in spring quadruple the chance of prolonged energy droughts: reduced snowpack and rainfall lower hydro availability but also dry out subsoils, increasing the chance of heatwaves and therewith extending the energy problems into summer. We identify and quantify three compounding energy/climate conditions and the associated characteristics and risks of multi-year energy droughts, crucial for informing future energy system design.

随着欧洲可再生能源产能的扩大，电力系统面临着能源干旱风险的增加——低产量时期与高需求时期同时发生。我们通过计算 1,600 年的每日生产和需求来评估天气变化引起的电力变化特征。重点关注五个欧洲国家（根据包括水电在内的能源结构选择），我们发现能源干旱是由对能源和气象系统造成（暂时）复合影响的过程造成的。这些可能会将短期干旱变成长期未满足的能源需求。例如，春季水库入水量较低，导致长期能源干旱的可能性增加四倍：积雪和降雨量减少，水力供应量降低，但也使底土干燥，增加热浪发生的可能性，从而将能源问题延长到夏季。我们确定并量化了三种复合能源/气候条件以及多年能源干旱的相关特征和风险，这对于为未来能源系统设计提供信息至关重要。