Electrical lines and facilities are a necessary part of the infrastructure within any community, just like roads, water and sewer facilities.
High-capacity transmission lines carry electricity long distances, such as from the Boardman Plant in eastern Oregon to the Willamette Valley. Transformers in transmission substations near the generation facility increase the voltage for more efficient transmission over long distances. These voltages are very dangerous to humans, which is why transmission lines are located on high towers.
As it gets closer to where it will be used, electricity is routed through transformers at distribution substations, which lower the voltage for safety in populated areas. Often the electricity is lowered further via neighborhood transformers before passing into end-users’ service lines. Those voltages typically are 120/240 volts for homes and 480 volts for business and industry.
Key principals of delivering electricity
Electricity can’t be easily stored.
So the system must always be able to instantaneously respond to fluctuations in demand. Providing the exact amount of electricity being demanded at any given instant keeps the system from crashing, which can cause blackouts.
Electricity will seek the path of least resistance.
That could be through a wet tree branch touching a power line or a connected utility system using some of the same lines. Read more about safety around electricity.
Disturbances travel quickly
The current on electrical lines moves at the speed of light. A sudden disturbance travels just as quickly. Since the country’s transmission system is interconnected, if a tree hits a power line in Oregon it can quickly interrupt service in Los Angeles. So, everyone one on a transmission system must cooperate and be ready to react to one another’s actions and disturbances.
Electricity must travel a circuit to keep the electrons flowing. If it’s interrupted, electrons will stop flowing. The electricity delivery system is essentially a giant circuit: electricity passes through the consumer’s meter, into the building’s wiring, to the appliances, and back the way it came to the generation facility. The health and adequate capacity of Oregon’s transmission system is therefore crucial to powering our future.
Transmission lines operate somewhat like interstate freeways that move large volumes of traffic. The lower-capacity distribution lines operate like streets that crisscross communities and neighborhoods. When freeways get congested, everything slows down. In a similar way, transmission lines get congested and electricity cannot flow as reliably from the source of generation to your home or business. Read more about how PGE is planning to ensure transmission reliability to meet our growing energy needs.