Diablo Glaciers Photo

Most of the electricity we provide to customers comes from several utility-owned hydroelectric resources located in the Pacific Northwest. To make up the difference, we purchase any additional power needed from other energy providers.

City Light Energy Resources

Map showing the sources of City Light's energy

Map Key:

Blue color swatchCity Light owned hydropower

Orange color swatchTreaty rights from British Columbia

Black color swatchLong-term hydropower contracts (CBH is Columbia Basin Hydropower)

Yellow color swatchOther long-term contracts

To maintain our carbon-neutral status, we purchase Renewable Energy Credits (RECs) to offset carbon from energy purchased from other providers. We also invest in energy conservation that minimizes electricity demand.

How Energy Gets to Your Home or Business

Electricity is delivered to your home or business through our extensive network of transmission towers, substations, and distribution lines.

Graphic of a dam7 hydroelectric facilities
owned by City Light
Graphic of an electrical substation16 major substations
in City Light service territory

Graphic of a transmission tower2,330.9 miles
of distribution circuit

Graphic of an electrical meter515,107 meters
in City Light service territory

Power Transmission and Distribution

Graphic showing how power is transmitted from a dam to a home

  1. Power is generated from the dam and powerhouse
  2. Substation transformer steps up the voltage for transmission
  3. Transmission lines carry electricity long distances
  4. Neighborhood substation transformer steps down voltage
  5. Distribution lines carry electricity to residents
  6. Transformers on poles step down electricity before entering residence
  7. Service lines deliver power from the pole to the residence

Where Does Your Power Come From?

Seattle City Light Power Mix

Over 78% of the power we deliver is generated from carbon-neutral hydroelectricity. In a typical year, about 40% of our power comes from our fully owned hydroelectric projects on the Skagit and Pend Oreille Rivers. The remaining power is generated from a mix of power sources purchased from the Bonneville Power Administration (BPA) and other renewable sources.

City Light’s power supply portfolio does not include coal or natural gas resources. However, we do make market purchases when necessary. These purchases may incidentally include coal or natural gas resources. Any emissions associated with unspecified market purchases are offset through our greenhouse gas (GHG) neutrality policy.

1 Fuels from wholesale market purchases are unspecified because current power market practices don’t require the identification of the specific generating source at the time of sale.
2 This fuel represents a portion of the power purchased from Bonneville Power Administration.
Source: 2023 Washington State Department of Commerce Utility Fuel Mix

City Light

Dawn Lindell, General Manager and CEO
Address: 700 5th Ave, Seattle, WA, 98104
Mailing Address: PO Box 34023, Seattle, WA, 98124-4023
Phone: (206) 684-3000
SCL_ExternalComms@seattle.gov

Seattle City Light was created by the citizens of Seattle in 1902 to provide affordable, reliable, and environmentally responsible electric power to the City of Seattle and neighboring suburbs.