Whether current flows from a grounded generator into the earth depends entirely on the mental model one holds about what the earth represents in an electrical circuit.

In a three-phase AC power system, during a ground fault (such as a tree branch knocking down a power line), the weak electromagnetic coupling that normally keeps phase-to-ground voltages balanced is overpowered, causing all phases to experience a voltage shift with respect to ground, though phase-to-phase voltages remain unchanged.

Adding salt water to saturated soil dramatically increases its electrical conductivity, allowing significant current to flow, because electrolytes in the salt water enable the soil to conduct electricity more effectively than pure water.

Power line technicians are often encouraged to hop on one foot away from a ground fault to reduce the chance of step potential, because hopping minimizes the voltage difference between the two feet and thus reduces the current flowing through the body.

Engineers designing power plants, substations, and transmission lines must calculate the maximum safe touch potential and step potential limits for humans and design grounding systems to ensure these limits are never exceeded.

The Pacific DC Intertie carries power from the Pacific Northwest into Los Angeles and is equipped with elaborate grounding systems: in Oregon, over 1000 electrodes are buried in a ring with a circumference of 2 miles (3.2 kilometers), and in California, huge electrodes are submerged in the Pacific Ocean a few miles offshore.

DC electrode systems create magnetic fields that can affect compass readings and magneto-sensitive fish like salmon and eels, and ocean electrodes can cause electrolysis, breaking down seawater into toxic chemicals like chloroform and bromoform.

It is not possible to identify specifically which power plant serves a particular city or building because power gets intermingled on the grid, flowing along transmission lines according to the difference in electrical potential rather than following fixed routes.

Current in grounded systems flows through the ground (the earth itself) as a return path, not into the ground as a sink; the ground is essentially just another wire, albeit a high-resistance one compared to copper or aluminum conductors.

In small, low-voltage devices like battery-powered toys, the difference in electrical potential between components and the actual earth is not important, but this is not true for high-voltage systems connected to the grid because the phase-to-ground voltage differences become significant safety and cost concerns.

In appliances with metal casings, current flowing from a live wire into the metal case creates a hazard, but adding a grounding conductor (parallel low-resistance return path) to the housing allows fault current to flow at high levels, triggering a breaker to shut off the circuit and preventing fire or electric shock.

Lightning is a type of static electricity that flows out of the ground into the atmosphere (most frequently) or into the ground from the atmosphere, restoring an imbalance of charge; the mechanism is not fully understood.

Dry sand is a poor conductor of electricity, and soil and rock conductivity varies widely based on soil type, season, weather, temperature, and moisture content, making the resistance of the earth connection highly variable and dependent on local conditions.

Electricity does not take the path of least resistance; rather, it takes all paths available in accordance with their relative conductivity, meaning that current distributes proportionally across multiple paths.

Most substations are equipped with a grid of buried conductors rather than a single grounding electrode to minimize resistance in the earth connection, reducing voltage gradients and thus step and touch potentials.

Stray electrical currents flowing into pipelines and other buried structures through ground return paths can cause corrosion, and return currents from traction motors in electric trains can flow into ground and corrode adjacent pipelines while occasionally interfering with buried telecommunication lines.

The E2 pulse from a nuclear EMP is generated from the interaction of gamma rays and neutrons and is roughly comparable in strength to a lightning strike, often being less powerful than many lightning strikes from high-altitude nuclear detonations.

In transformers, there is a relationship between how much current flows and the strength of the resulting magnetic field, but this relationship breaks down at a saturation point beyond which additional current won't create much further magnetism to drive current on the secondary winding.

Due to Earth's magnetic field, the maximum amplitude of an E1 pulse occurs slightly south of ground zero in the northern hemisphere, creating a pattern called a smile diagram.

Modern digital protective relays are full of circuit boards, screens, and microelectronics that are particularly susceptible to electromagnetic interference, and most countries have strict regulations about the strength and frequency of electromagnetic radiation permitted on the airwaves.