The energy in a green plant is stored as chemical energy. During photosynthesis, green plants convert light energy from the sun into chemical energy stored in the bonds of sugar molecules, primarily glucose. This chemical energy is then available for the plant's cellular activities, growth, and metabolism. The plant can also store excess glucose in the form of starch, a complex carbohydrate, for longer-term energy storage. Thus, the kind of energy store in a green plant is chemical energy stored in sugars and starches synthesized during photosynthesis.