Sugar.
It will give you a quick burst but will come back to make you very tired afterwards. Or caffine.
Glucose
Bananas are a good source of natural sugars, carbohydrates, and potassium that can provide a quick and lasting boost of energy. They are a popular choice for athletes and those needing a quick energy boost.
The primary substance that supplies us with energy for daily activities is glucose. Glucose is derived from the carbohydrates we consume in our diet and is the main source of energy for our bodies.Cells use glucose to produce adenosine triphosphate (ATP), which is the energy currency of the body.
Fire is not a source of energy it is a manifiestion of the release of energy.
Carbohydrates are the main source of energy for the body, providing fuel for daily activities. When broken down, carbohydrates are converted into glucose, which is used by the cells as energy.
Canada
For us here on Earth, the prime source of energy is the Sun.
Wind
Biomass is the source of almost half of America's renewable energy.
Hydropower
Adrenaline, also known as epinephrine, is the substance responsible for providing quick instant energy to deal with emergency situations by increasing heart rate, boosting oxygen to the brain and muscles, and releasing glucose into the bloodstream for rapid energy production.
most likely, it's coal