Key technologies for smart energy systems: Recent developments, challenges, and research opportunities in the context of carbon neutrality

Energy crisis and environmental pollution have expedited the transition of the energy system. Global use of low carbon energy has increased from 1:6.16 to 1:5.37. Smart energy systems have received significant support and development to accelerate the development of smart cities and achieve the carbon neutrality goal. As a result of analyzing recent related publications and weighing their merits and downsides, it is determined that a more comprehensive and objective analysis of the main technologies underlying smart energy systems is necessary for the context of the new era. We report thoroughly on the six important hotspot technologies in smart energy systems, and undertake a comparative analysis of each technology's performance features, application status, and challenges. The ten key obstacles to developing a smart energy system are examined in terms of technology constraints, the social environment, human survival, and extreme climate circumstances. The four opportunities that smart energy systems confront in the digital age are examined in terms of governmental support, technology innovation, and public participation. The purpose of this research is to advance the creation of smart energy systems and the sustainable development of society in two ways: i) Smart energy system research should begin with a combination of technological innovation and practical application; ii) Key technologies in smart energy systems should consider the needs of people's livelihoods to evolve in a more intelligent and diverse path.