Electricity 101: How the grid works

How Arizona fits in, and how SRP is modernizing our part of the electrical grid

Animation of power moving from power plants, solar panels and wind turbines into transformers and power lines to provide energy to homes and businesses

Chances are, you don’t think about the electricity that powers your home too often. Much like the air we breathe, power is just “there” every time you flip a switch or plug something in. But in reality, the electrical grid is a highly complex system made up of power generating stations, transmission lines, substations, transformers, power lines and infrastructure that deliver electricity to homes, businesses and industries. You see the power grid every day, but it’s such a staple of life, you might barely notice it anymore.

How Arizona fits into the power grid

The U.S. actually has three major grids:

  1. The Western Interconnection
  2. The Eastern Interconnection
  3. The Electric Reliability Council of Texas

Arizona belongs to the Western Interconnection, which serves over 80 million people, spans more than 1.8 million square miles and includes approximately 136,000 miles of transmission lines. It connects 14 U.S. states, the Canadian provinces of British Columbia and Alberta, and the northern portion of Baja California in Mexico.

How the electric grid works

The combined U.S. grid is the largest interconnected machine on the planet, but getting electricity into your home can be broken down into three key steps:

  1. Generation. Electricity starts at a generator, which can be powered by burning fossil fuels, running wind turbines, capturing the sun’s energy via solar panels, collecting water energy in hydroelectric dams or harnessing it from nuclear reactors.
  2. Transmission. After power is generated, it moves into a transmission substation that uses a transformer to “step up” (or increase) the power to extremely high voltages for transmission across long distances. Those very large power lines you see are transmission lines. This power is then stepped down (or decreased) at a transformer in a substation closer to your home.
  3. Distribution. From the substation, electricity travels through wires, either through overhead or underground lines, before being stepped down again via a small transformer attached to the pole or on the ground. If your lines are underground, you or one of your neighbors might even have one of these little transformers in your yard.

From there, you can use this power to light your home, prepare your meals, keep yourself cool during those hot Arizona days, binge-watch your favorite shows and maybe even power your electric car.

Evolution of the grid

As you might expect, the same grid that was designed to simply keep the lights on in the early to mid-1900s doesn’t work as well for us today. That’s why SRP and other utilities around the country are continuously working to modernize the grid to meet our changing needs.

Today’s enhanced, more efficient grid features two-way communication technology that enables you to do things like check your energy use on a daily basis in My Account or the SRP Power mobile app and receive eNote alerts and reminders for outages, bill projections and more.

It also operates more reliably and efficiently, allowing SRP to plan and anticipate energy demand to avoid drops in power quality and speed power restoration after an outage. It improves the ability to serve future economic development and lets us integrate more renewable energy into the mix (including excess energy generated by our customers who have solar panels installed on their roofs).

Learn more about how SRP is preparing for the Valley’s future energy needs, and read our 2035 Sustainability Goals.

Nicole Denton

Nicole Denton

Nicole is an online communications strategist at SRP. She has called Arizona home since 2013 and currently resides in Mesa with her husband, Michael, and their three rescued pets. She's a University of Tennessee grad and loves college football. When she's not working or cheering on the Vols, she enjoys experimenting with fashion and home decor.

More Posts