Energy Meter

The Energy Meter is a crucial feature of the Heads-Up Display in all Metroid games. Located in the top left or the very top of the screen, it displays the number of energy units that Samus has, while also displaying her Energy Tanks above this number. The meter is represented by two digit numbers and the word "Energy" (although in the original Metroid, "EN" is displayed, and Metroid: Zero Mission only displays the numbers). The meter records up to 99 units per Tank. The Prime games and Metroid: Other M feature an energy bar along with the number digits, which gradually shrinks and refills as Samus loses and regains energy. If her energy is drained completely, Samus will die or the Power Suit will be unable to protect her, leading to the Game Over screen. In 3-D games, if energy drops to a low level, the HUD will beep and flash a warning to Samus. To stay alive, Samus must keep the shielding of her Power Suit charged by obtaining Energy Capsules, using Energy Charge or Recharge Stations or Save Stations or entering her Gunship.

Near the end of Metroid Prime 3: Corruption, the Energy Meter is changed into a Phazon level, representing Samus' level of Phazon corruption. To avoid dying of Terminal Corruption, Samus is required to drain her energy into objects or by collecting Anti-Phazon Units.

In Metroid Prime: Federation Force, the Federation Marines have Energy Meters as well, albeit on the left side of the HUD. Their Mech suits are not known to be able to expand the amount of energy they can have.

Metroid II: Return of Samus
"The units of energy that Samus currently has. Each filled tank holds 100 units."

Super Metroid

 * Energy Display:This displays Samus' remaining energy. When it falls to "0", the game is over.
 * Energy Tank Display:This displays the number of energy tanks that Samus is carrying. The amount of energy contained in a single tank is 99 units.

Metroid Fusion
"Amount of energy Samus possesses. If this reaches 0, the game is over."

Metroid Prime/Metroid Prime 2: Echoes
"The numeric display and horizontal gauge track the amount of energy in Samus's Energy Tank. The highlighted squares above the main energy gauge indicate Energy Tanks that Samus has in reserve."

Metroid: Zero Mission

 * Energy:"This indicates how much energy Samus has remaining. If this number reaches zero, the game will end."
 * Energy Tanks:"These dots show how many Energy Tanks Samus has. Each one contains 100 energy units."

Metroid Prime Hunters

 * Remaining Energy:"Samus's current energy level. If the Energy Gauge reaches zero, the game is over."
 * Energy Gauge:"When Samus receives damage, the Energy Gauge of each tank drops."

Metroid: Other M

 * Energy (health) Level:"If you run out of energy and your Energy Tanks are empty, your game will be over (see p. 18)."
 * Energy Tank count:"One tank contains 99 units of energy. You will acquire more Energy Tanks as you progress through the game (see p. 19)."