Tag: Specific energy

Liquid hydrogen fuel has a much lower volumetric energy density than gasoline, even though it possesses a higher gravimetric energy density or specific energy. This illustrates a key principle: the factors influencing energy density are complex and vary depending on whether the metric is based on mass or volume. A material’s composition, its physical state, and the overall system design are all critical determinants.

A single gram of matter, if fully converted to energy via Einstein's equation ($E=mc^2$), contains 89.9 petajoules of energy. In a matter-antimatter annihilation reaction, the total energy released per gram of *antimatter* is twice this amount, making antimatter the most energy-dense substance known. However, this is a theoretical peak, with more practical sources also offering incredible power.

Did you know that liquid hydrogen boasts a gravimetric energy density over three times higher than gasoline, though it has a much lower volumetric density? This fundamental distinction helps illustrate what energy density is—a crucial concept for comparing and developing energy storage systems.

According to Einstein's famous equation, $E=mc^2$, the greatest possible amount of energy is stored within mass itself, released through annihilation. While many substances contain immense energy, the ultimate winner for the greatest amount of energy per gram is antimatter.