Digitalization-related services and applications are based on the information and communications technology (ICT) ecosystem and today encompass nearly all areas of society and economic sectors. They have many opposing effects regarding energy and electricity consumption, on the one hand, and the corresponding CO2 emissions, on the other. Whereas direct effects are related to the production, operation, and disposal of ICT elements, which increases electricity consumption, the indirect effects related to the usage of ICT elements are ambiguous. Our analysis aims to inform policy decision-makers about the actual climate relevance of the ICT ecosystem by providing a comprehensive and structured review of the related streams of the literature. From our balanced reading of the related empirical literature, we infer that higher ICT intensity implies mixed results regarding electricity and energy consumption, but tends to lower CO2 emissions. The latter is particularly true for developed countries. Our main findings therefore suggest that ICT elements can give rise to positive environmental effects for society, particularly within developed countries where the usage of ICT elements is high.