How Do Eels Generate Electricity?

How Do Eels Generate Electricity

Quick Answer

Electric eels generate electricity through specialized cells called electrocytes, organized in series within their electric organs. These cells function similarly to batteries, creating a voltage difference that can be discharged to produce electric shocks. This ability allows electric eels to stun prey, defend against predators, and navigate their environment.

Understanding Electrocytes

Electric eels possess three main electric organs: the main organ, the Hunter’s organ, and the Sach’s organ. These organs are packed with electrocytes, which are modified muscle cells. Unlike typical muscle cells that contract to move, electrocytes generate electric charges.

How Electrocytes Work

  1. Resting State: In their resting state, electrocytes maintain a potential difference across their membranes, with the inside of the cell being negatively charged relative to the outside.
  2. Activation: When the eel decides to discharge electricity, its nervous system sends a signal to the electrocytes.
  3. Ion Movement: This signal triggers the opening of ion channels in the electrocyte membranes, allowing sodium ions to flow into the cells and potassium ions to flow out.
  4. Voltage Difference: The movement of ions rapidly changes the electric potential across the electrocyte membranes, generating a voltage difference.
  5. Series Connection: Thousands of electrocytes are stacked in series within the electric organs, amplifying the voltage to produce a significant electric discharge.

The Role of Electric Organs

Main Organ

The main organ generates the high-voltage discharges used to stun prey and deter predators. It can produce shocks of up to 860 volts, making it known as the most powerful bioelectric generator.

Hunter’s Organ

The Hunter’s organ assists the main organ in producing high-voltage discharges. It also affects the eel’s ability to navigate and locate prey through electrolocation.

Sach’s Organ

The Sach’s organ generates low-voltage discharges used primarily for navigation and communication. These discharges help the eel sense its surroundings and communicate with other eels.

Electrolocation and Communication

Electric eels use their electric discharges as weapons and as sophisticated sensory systems. This process, known as electrolocation, allows eels to detect objects and prey in their environment by sensing distortions in the electric field they generate.

How Electrolocation Works

  1. Electric Field Generation: The eel emits a low-voltage electric field around its body.
  2. Field Distortion: Objects in the environment, especially conductive ones, distort this electric field.
  3. Detection: Electroreceptors in the eel’s skin detect these distortions, allowing the eel to “see” its surroundings even in murky waters.


Electric eels also use low-voltage discharges to communicate with each other. These signals can convey information about territory, mating readiness, and other social interactions.

High-Voltage Discharges for Hunting

When hunting, electric eels use high-voltage discharges to incapacitate their prey. This process involves a series of rapid discharges that cause involuntary muscle contractions in the prey, effectively immobilizing it.

Hunting Strategy

  1. Detection: The eel uses low-voltage discharges to locate prey.
  2. Stunning: Upon detecting prey, the eel switches to high-voltage discharges to stun the target.
  3. Capture: The eel easily captures and consumes the immobilized prey.

Scientific and Practical Implications

The study of electric eels has provided significant insights into bioelectricity and has inspired various technological advancements. For instance, the mechanism of electrocytes has influenced the design of batteries and bioelectronic devices.

Technological Inspirations

  1. Battery Design: The series arrangement of electrocytes has inspired the design of high-efficiency batteries.
  2. Medical Devices: Research on electric eels has led to the development of bioelectronic devices, such as pacemakers and other medical implants.

Final Thoughts

Electric eels are fascinating creatures with a unique ability to generate electricity. This capability is crucial for their survival and offers valuable insights into bioelectricity and its applications. Understanding how eels generate electricity can inspire new technologies and deepen our appreciation for the complexity of life.