5-10m read  |  # ElectricityGeneration #HighVoltage #DistributeElectricity

Tons of people are curious about how large electricity companies like Meralco generate and deliver electricity for everyone. So, I decided to write for everyone and in short, explain how electricity is made and shared for everyone to use.

Meralco's Available Generation Options - Solar and Coal are shown

Electricity is an important resource nearly all families in the Philippines need to keep living - it keeps their fridges and homes cold, their stoves functional and ensures a comfortable lifestyle reducing the need for manual work in place of physical motors - the stove you use may be electrical, boiling water is now possible via kettles and fans keep you cool without having to wave one of those classic hand fans anymore.

So, how is electricity generated exactly?

Electricity generated at regional power facilities (e.g., Rockwell Center, or Manila Thermal Power Plant delivering energy to the Luzon Grid) is produced at moderate voltages (13.8 kV to 22 kV). To be able to transport this electrical power across long distances from provinces to rural agricultural communities, step-up transformers increase the voltages to to bulk transmission levels (up to 230 kV). 

A step by step simplified explanation of the transmission of electricity. All images sourced online. Some may be AI.

Why use higher voltage?

Higher voltage transmission reduces the electric current needed to deliver power and minimizes thermal energy loss along long high-voltage transmission lines. This will ensure bulk energy is delivered efficiently to delivery-point substations (e.g., Taguig and Manila EHV/HV substations) before being stepped down for distribution to the consumers.

Well, how do they deliver it across Metro Manila so easily?

The urban distribution utilities (like MERALCO operating across Manila, Makati, Pasay, and Taguig) utilize major delivery points and distribution substations to step-down high transmission voltages (230 kV or 115 kV) to sub-transmission and primary distribution levels (34.5 kV or 13.8 kV). Line-mounted distribution transformers step down the primary voltage to standard single-phase 230 V. Electrical utility meters track total energy consumption in kilowatt-hours(kWh), letting utilities to monitor local power demands, manage grid loads, and safely integrate grid-tied rooftop solar Net-Metering fields.

So... in short?

Electricity begins at the generators, where actual power is converted from natural sources, such as coal, hydro or solar. Voltages from these generators are low, typically at 600V. In order to transmit power further without losing much current due to resistive losses, we need to step up the voltage, typically at a few hundred kilovolts (~140KV is the standard). Once we do that, we can send it through long distances through transmission lines. On the way, substations manage the flow of power to be sent through distribution lines in cities and neighborhoods which also comes with the step-down transformer, lowering it to a few KVs. Finally, they're sent through distribution lines and transformers along the way reduce it to 240V, making it suitable for household use.