Power Facts

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Stand-alone electric systems have special challenges: We have to be more reliable

Meeting Electricity Demand

On the Mainland, power utilities can get power from another utility, often in a different state, through a grid of interconnected transmission lines.

In Hawaii, each island generating system must stand alone without backup from other utilities. Hawaiian Electric must:

  • Be more reliable and self-reliant than other utilities.
  • Have enough generators to produce power during "Peak" time - or when people use the most electricity
    (usually after work during weekdays).
  • Install more reserve generation to account for generating units taken down for regular maintenance and to cover the potential unplanned loss of the largest generating unit.

Generating units are run efficiently to meet customer needs

Baseload units run 24 hours a day. They are the most fuel and cost efficient.

Cycling units are started when demand goes up and shut off when demand goes down.

Peaking units can be quickly started. They are more expensive to operate and limited to peak hours (usually 5 p.m. - 9 p.m.) when people use the most electricity.

We keep costs down while keeping product quality high

In planning the generation of power, we use the more efficient and less expensive baseload units whenever possible. We use higher cost peaking units only as you need them.

We're also using preventive and predictive maintenance to keep each generating unit at optimum performance.

We generate and transmit power reliably and efficiently, while maintaining a commitment to operate in a safe and environmentally responsible manner. We are committed to complying with all safety and environmental protection requirements for the sake of our customers, employees, and our community, working closely with the State of Hawaii and the U.S. Environmental Protection Agency.

How the Hawaii Power Grid Works

This video provides an overview of the unique challenges of operating electric grids in Hawaii. It was produced independently by the YouTube channel Practical Engineering.

Energy conservation

"How the Hawaii Power Grid Works" YouTube, produced independently by Practical Engineering, March 19, 2024.