From generation to appliance
Trace a conventional large-source supply path, then notice where real networks branch and vary.
Convert a primary source
Begin with energy in moving water, wind, fuel, sunlight, or another source. A generator or photovoltaic system converts some of that energy into electricity. This journey uses a large grid-connected source for clarity; smaller sources can enter the network much closer to the consumer. The upstream resource remains a condition on what can be produced.
A primary energy source becomes electrical output.
Conversion makes energy available in the form the network can transfer.
Read the complete journey
- 1
Convert a primary source
Begin with energy in moving water, wind, fuel, sunlight, or another source. A generator or photovoltaic system converts some of that energy into electricity. This journey uses a large grid-connected source for clarity; smaller sources can enter the network much closer to the consumer. The upstream resource remains a condition on what can be produced.
Notice: A primary energy source becomes electrical output.
Explore Electricity generation
Why: Conversion makes energy available in the form the network can transfer. - 2
Raise the voltage
In a conventional AC supply path, a transformer raises the voltage for transmission. For a given power transfer, higher voltage allows lower current, reducing resistive heating in the conductors. The transformer does not add energy. It has its own losses and must operate within equipment ratings. High-voltage equipment also needs appropriate insulation and clearances.
Notice: Voltage rises while required current can fall for the same power.
Explore Transformers
Why: Lower current can reduce resistive losses on a long transfer. - 3
Share a connected network
Bulk power moves through a network of lines and substations. Multiple generators and demand centres are connected at once. The highlighted route is a way to learn the roles, not an exclusive electrical lane. In AC networks, power distributes among available paths according to electrical conditions. An interruption can change flows on lines beyond the affected location.
Notice: The physical network contains parallel paths.
Explore Transmission networks
Why: Interconnection allows shared supply but introduces coupled operating constraints. - 4
Change scale at a junction
At a supply substation, transformers may lower voltage while switchgear and protection connect and manage circuits. Instruments provide information about the network’s state. Some substations mainly switch rather than transform. Their arrangement depends on the role they play within the local system. Protection and measurement support operation even when no voltage change occurs.
Notice: A controlled junction links different sections of the network.
Explore Substations & protection
Why: Transformation and switching adapt the connection to its next role. - 5
Branch towards buildings
Distribution feeders spread across neighbourhoods, with further voltage transformation where needed. Overhead lines and underground cables are both common. Local solar and storage can add branches and reverse some flows, so a simple left-to-right diagram is a starting case rather than a universal operating pattern. A single highlighted branch hides many simultaneous flows elsewhere.
Notice: The supply branches towards many smaller connections.
Explore Distribution networks
Why: Distribution brings the service to individual loads and local sources. - 6
Cross the measured boundary
At the property connection, a meter records energy imports and, where supported, exports. The building installation connects appliances to the supply under local electrical standards. Metering, protection, and wiring have different jobs, even when their equipment is located near one another. Its position does not make it a substitute for the installation’s protective equipment.
Notice: Energy crosses a defined measurement boundary.
Explore Meters, power & energy
Why: Metering records a quantity needed for accounting and understanding use. - 7
Deliver the useful service
The appliance turns electrical energy into light, heat, motion, or electronic work. Some energy becomes unwanted heat along the supply chain. The complete story therefore includes both the useful service and the conversions and losses that made it possible. Circuit behaviour is more detailed than our one-line drawing. Energy losses remain part of the full accounting.
Notice: Useful output appears as heat, light, motion, or electronic work.
Explore The appliance & its circuit
Why: The final conversion links network operation to an everyday purpose.
Why does raising voltage for transmission not create extra energy?
Reveal the explanation
A transformer changes the relationship between voltage and current. Ideally power is conserved, while real equipment has losses; the higher voltage can reduce current and conductor heating for the same transfer.
Sources & further reading
Original explanations informed by these sources. Diagrams are conceptual; local systems differ.
- How electricity is generated U.S. Energy Information Administration · 2023-10-31 · Source & rights record
- Batteries, circuits, and transformers U.S. Energy Information Administration · Not stated · Source & rights record
- How electricity is delivered to consumers U.S. Energy Information Administration · Not stated · Source & rights record
- Electricity 101 U.S. Department of Energy · Not stated · Source & rights record
- Measuring electricity U.S. Energy Information Administration · Not stated · Source & rights record
Another way through the system.
Switch on a kettle
One small switch. A connected system.
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Follow energy through conversion, storage, and time.
Move a load, change the peak
Explore flexibility without confusing power with energy.