Russia’s all-out invasion of Ukraine demonstrated the risks of depending on single fossil-fuel suppliers. From spring 2022 onwards, Russia began to reduce or cut off gas supplies to its European customers in an attempt to blackmail them into changing their policies on Ukraine. Europeans, in turn, had to quickly find alternative suppliers to ensure the stability of their electricity systems and gas-using industries Renewable energy sources are therefore of practical importance for energy security – and investments in renewables and the expansion of their installed capacity have mitigated the effects of the energy crisis since 2021 ufabet