Decarbonization pathways have emerged as a pivotal element of global climate change mitigation strategies. Energy system modelling is widely recognized as a tool to support the design of informed energy decarbonization policies. However, the development of energy models heavily relies on high-quality input data, which may pose significant challenges in developing countries where data accessibility is limited, incomplete, outdated, or inadequate. Moreover, while models may exist in countries, these are not publicly available; therefore, details cannot be retrieved, repeated, reconstructed, interoperable or auditable (U4RIA*). This paper presents an open techno-economic energy dataset for Colombia that is U4RIA-compliant as it can be used transparently to model decarbonization pathways and support energy planning in the country. Despite being country-specific, most of the data is technology-based and thus applicable to other countries. Diverse sources, assumptions, and modelling guidelines are described to facilitate the creation of new datasets. The dataset enhances the availability of energy data for policymakers, stakeholders, and researchers, not only in Colombia but also in other developing countries.