Do mitochondria capture energy?
No the mitochondria does not capture energy however it does release it as a byproduct of cellular respiration
Chloroplasts must capture the sunlight during the day and make it into Glucose, STARCH, or store it in the mitochondria as ATP energy. After this happens they will then rely on the mitochondria for glucose at night. Either way, the plant must have energy at all times. Hence why it is stored in the mitochondria.
They capture energy from food broken down to form ATP (adenosine triphosphate) molecules. ATP provides the energy for all cellular work and every living cell requires a constant supply of ATP for its activities. Because the mitochondria supply most of this energy, they are referred to as the "powerhouse" of the cell.