The COVID-19 pandemic represents not just a global health crisis, but may signal the beginning of a new era of economic activity, the potential consequences of which we currently do not fully understand. In this context, the mid-to-long-range impacts of the pandemic on the energy sector have been studied extensively in the last few months. Despite these efforts, the pandemic still raises many open questions concerning the long-term operation and planning of power systems. For instance, how will the pandemic affect the integration of renewable energy sources? Should current power system expansion plans change in light of the COVID-19 pandemic? What new tools should be provided to support system operators during global health crises? It is the purpose of this paper to better understand the many aspects of these open questions by reviewing the relevant recent literature and by analyzing measured data. We point out the main challenges that the pandemic introduced by presenting patterns of electricity generation and demand, frequency deviations, and load forecasting. Moreover, we suggest directions for future research that may assist in coping with the mentioned challenges. We hope that this paper will trigger fruitful discussions and encourage further research on these important emerging topics.

Decarbonizing energy-intensive and other hard-to-abate sectors remains essential for meeting climate targets, yet these sectors continue to depend on fuels for high-temperature heat, chemical feedstocks, and energy-dense transport applications. This roadmap assesses the potential role of renewable synthetic fuels (RSFs) in supporting this transition, with a primary focus on the European context and on sectors including steel, cement, glass, aviation, shipping, and power generation. It reviews the current status of RSF combustion science, the high-fidelity experimental and numerical data needed to understand fuel behavior under relevant conditions, and the emerging hybrid physics-based and data-driven modeling approaches that can accelerate progress. Particular attention is given to digital twins and related cyber-physical tools as enabling technologies for process optimization, monitoring, scale-bridging, and industrial implementation. The roadmap also examines practical deployment barriers, including fuel availability, infrastructure, safety, regulatory frameworks, policy barriers, and data integration challenges. Developed in the framework of the CYPHER COST Action, it highlights that large-scale RSF deployment will require coordinated action across research, industry, and policy, together with stronger business cases, demand-stimulating policies, and workforce development.