This study on the Estonian lower secondary (7-9th grade) science curricula, is seen as an important framework for educators preparing students as tomorrow's citizens able to reflect on sustainable energy development. As the curriculum is taken to be the major document allowing insights into Estonian educational standards, this study identifies components within the intended lower secondary science curricula for subjects of biology, chemistry, earth science, physics, and interdisciplinary science. Using document analysis, verbs associated with career-related learning outcomes are detected, allowing the relatedness of the energy conceptualizations and determination of their cognitive level utilizing SOLO (Structure of Observed Learning Outcomes) taxonomy. A team of coders identify a total of 782 learning outcomes across three learning domains: psychomotor (176), affective (32), cognitive (574) at unistructural (33), multistructural (225), relational (276), and extended abstract (40) levels. The majority of energy concept learning outcomes (274) are identified in the source (form) and transfer (transform) categories. Very few career-related learning outcomes are detected with the science education relevance dimensions (individual, societal, career). The suitability of the findings is discussed. The current analyzing method can be applied to other educational disciplines for raising awareness of disciplinary crosscutting concepts.