What molecules can be used for long-term energy storage?

Energy can be stored as lipids, mainly fats for a long- term.

Explanation:

Energy can be stored in the body in the form of carbohydrates or lipids (in the form of fats). However, carbohydrates are used for short-term energy storage whereas fats are used for long-term energy storage. As carbohydrates are readily digestible, hence they are an excellent source for quick release of energy.

The energy content per gram of fats is relatively greater then the energy content per gram for carbohydrates. Hence, making them ideal for storage.