solar energy
太 · 4 strokes
Addition of a dot to 大 (dà; big) to mean "very" or "extremely".
阳 · 6 strokes
The traditional characters 陰 (Yin) and 陽 (Yang) were simplified to 阴 and 阳. In Chinese philosophy, the moon (月) corresponds to Yin (阴) and the sun (日) corresponds to Yang (阳).
能 · 10 strokes
Pictograph of a bear. Based on the original meaning "bear". The meaning of this character has shifted over time to mean "strong" and "ability, power". Original form of 熊.