Preliminary studies demonstrate the availability of significant renewable energy potential in Spanish waters. Its use could contribute to achieving the recently updated national objectives for the generation of clean energy in the future National Energy and Climate Plan 2021–2030. Despite the different initiatives that were unsuccessfully proposed at the end of the 2000s, the current implementation of blue energy is practically zero in Spain due to the characteristics of the marine space, which limits the technical and economic viability of the projects. There are other factors, such as a complex regulatory framework, inadequate administrative processes, limited availability of information as well as social rejection of this type of facility. Like other Member States of the European Union, Spain is currently developing a process of maritime spatial planning (MSP) that should be concluded, according to RD 363/2017, with the approval of a maritime spatial plan (POEM) for each of the five existing marine demarcations. This planning will have consequences for the uses and activities of the marine environment, including marine renewable energies. It also provides an opportunity to address existing non-technical barriers and promote the deployment of blue energy facilities. This investigation studies the MSP landscape in Spain from a holistic perspective and analyzes the repercussions of future POEMs in the offshore wind sector and other marine renewable energies. It concludes by proposing a set of recommendations, based on previous experiences in other regions, aimed at facilitating the integration of clean energy policies in the future uses of this marine space.