Achieving the Paris Agreement’s 1.5 °C target requires a global-scale energy transition, reaching net-zero emissions by 2050. This transition demands not only a rapid expansion of renewable energy but also significant upfront energy investment, presenting potential trade-offs between near-term energy security and long-term sustainability. Assuming we cannot rely on as yet unproven negative emissions technology, reductions must be achieved directly, requiring fossil fuel phase-out, accelera...