Geoportal. The Ministry for Ecological Transition and the Demographic Challenge has launched a portal with information on energy certificates for buildings (https://edificioseficientes.gob.es/es).
Note. The tool incorporates a search engine in which you only have to enter the address of the property you want to consult (if it is a building, the different flats and premises will appear). If the property has a certificate, you will be shown the details and also:
Attention! This tool, as well as being useful for home sales or rentals, is also useful for other activities related to this field (construction companies, installers, maintenance services, financial services, architectural firms...).