Who runs the grid

Four roles, one dam

Explore Grand Coulee Dam ↗

Grand Coulee gives four different answers to "who runs it". The owner and the operator are the same federal agency, Bureau of Reclamation, which holds all 6,809 MW of operating capacity at the dam and runs every generator. That single-operator, many-owners shape comes straight from the survey: only the operator of a plant files the annual generator inventory, and ownership is reported separately, generator by generator [1]. Reclamation's part of the dam is three generating plants and a pump generating plant [9], which together produced 15,443,458 MWh in 2024.

The marketer is a third party. The Federal Columbia River Power System is a collaboration of three federal agencies: the Bonneville Power Administration was created to market the electricity, while dam operations stayed with the Corps of Engineers and Reclamation [5]. BPA markets wholesale power from the federal hydro projects, one non-federal nuclear plant and several small non-federal plants [4]. Federal law requires it to give preference and priority to public bodies and cooperatives [8], and it sells under long-term contracts: the Regional Dialogue contracts run out in 2028 [6], and Provider of Choice contracts take over for deliveries from October 2028 [7].

The balancing authority is a fourth thing again. Grand Coulee reports into Bonneville Power Administration, which holds 27,571.3 MW of operating capacity. A balancing authority keeps supply, demand and interchange in balance inside an electrically defined area [2]; it is an operating and accounting boundary, not a wire to a customer and not a service territory.

Who finally sells this energy to a household is not in the atlas. Owning, operating, marketing and balancing are four separate relationships, and only three of them are published here.

Grand Coulee on the capacity map ↗(opens the atlas in a new tab)

One company in every role

Explore Puget Sound Energy ↗

Puget Sound Energy holds every role at once. It owns 3,161.3 MW of operating capacity and operates 2,590.8 MW. It is also its own balancing authority: 2,960.3 MW of operating capacity reports into the Puget Sound Energy area. And it sells electricity to end users — the retail rows on its organization page come from the annual industry survey, which collects sales, revenue and customer counts by state, sector and balancing authority [3].

Owned is larger than operated, and the gap is one plant in Montana. Colstrip Steam Electric Station has six owners; the company that runs it is Talen Montana, an independent power producer that operates 1,647.4 MW and owns only 247.1 MW of it. Puget Sound Energy owns a share of Colstrip and runs none of it.

Being the balancing authority is not the same as owning what sits inside it, either. Puget Sound Energy's own Lower Snake River Wind Energy Project reports into Bonneville Power Administration, not into the utility's own area.

Because it is investor-owned, its rates and service are set by a state regulator. The Washington Utilities and Transportation Commission regulates investor-owned electric companies such as Puget Sound Energy, Avista and PacifiCorp, and does not regulate municipal, public utility district or cooperative utilities [10].

Everything Puget Sound Energy owns or operates ↗(opens the atlas in a new tab)

A city that owns its dams

Explore Boundary Dam ↗

Seattle City Light — the utility the city runs as Seattle City Light — is municipally owned. Washington law lets cities acquire, operate and maintain electric works and regulate the use, distribution and price of the electricity they sell [13], and City Light says it owns and operates several hydroelectric projects that typically supply more than half of its customers' power [21].

The largest is Boundary Dam, on the Pend Oreille River: 1,159.7 MW of operating capacity and 3,020,283 MWh in 2024. It runs under a federal licence. FERC licenses private, municipal and state hydroelectric projects [15] and issued Boundary a forty-two year licence in 2013 [22].

The city is also its own balancing authority. Seattle City Light holds 2,053.8 MW, close to the utility's owned total of 2,046.2 MW — an unusually tidy case in which owner, operator, balancing authority and retail seller are all one organization.

What differs from Puget Sound Energy is who sets the price. No state commission does: the Seattle City Council adopts City Light's rates by ordinance [14], and the state commission names Seattle City Light among the utilities it does not regulate [10].

Plants reporting to the Seattle City Light balancing authority ↗(opens the atlas in a new tab)

Two dams, two balancing authorities

Explore Grant PUD ↗

A public utility district is run by its own elected commission — three commissioners, or five in five-commissioner districts, elected by district for six-year terms [12] — and the district has full and exclusive authority over its own rates, free from the state commission [11].

Grant PUD owns 2,170 MW and operates 2,186 MW: more than it owns, because it runs small plants for others. Its two large dams are Priest Rapids Dam at 950 MW and Wanapum Dam at 1,220 MW, licensed together by FERC as the Priest Rapids Project [23].

Same owner, same operator, same river, one licence — and two different balancing authorities. Wanapum reports into the district's own balancing authority, Grant PUD, which holds 1,236 MW; Priest Rapids reports into Bonneville Power Administration. Balancing membership is reported plant by plant and does not follow ownership.

The output does not all stay in the county either. A 1998 federal order requires the district to sell a portion of the project's power, which it does through a public auction [24]. The district's own customers are not the only buyers, and the atlas does not say who the others are.

Every plant Grant County PUD owns or operates ↗(opens the atlas in a new tab)

An agency that owns a reactor and sells nothing

Explore Columbia Generating Station ↗

Energy Northwest is a joint operating agency, created by the Washington Legislature in 1957 and overseen by boards drawn from its member public utilities [18]. It is an owner and an operator and it is not a retail seller: it owns 1,324.4 MW of operating capacity and sells nothing to households.

Its largest asset is Columbia Generating Station, the region's only commercial reactor: 1,200 MW of capacity, 9,967,139 MWh generated in 2024, a capacity factor of 0.946 fraction. The chart shows the reported annual totals since 2015; what explains any particular year is not asserted from them. All of that electricity goes to the Bonneville Power Administration at cost, under a net billing agreement [19] — which is why BPA describes what it markets as the federal dams plus one non-federal nuclear plant [4].

Three different bodies decide different things here. The Nuclear Regulatory Commission holds the reactor licence [20]. FERC regulates wholesale sales and interstate transmission but does not regulate nuclear plants, retail sales or federal power marketing agencies [15]. And for balancing, the plant reports into Bonneville Power Administration.

Annual net generation · MWh. Bars below zero are negative net generation; a hollow mark means not reported. Missing years are not filled.

Columbia Generating Station on the generation map ↗(opens the atlas in a new tab)

A wind farm that sells its whole output

Explore Rattlesnake Flat ↗

Rattlesnake Flat, in Adams County, is owned and operated by Rattlesnake Flat Wind Farm, an independent power producer whose entire portfolio is this one plant: 144 MW of operating capacity, 415,933 MWh generated in 2024, a capacity factor of 0.329 fraction.

It reports into the Avista balancing authority, which holds 2,274.1 MW in all — and Avista, the utility that runs that area, owns none of the wind farm. Avista selected the project through a competitive solicitation and buys its output under a twenty-year power purchase agreement, expecting to recover the cost through its retail rates [25].

So the roles split across two companies. An independent producer owns and runs the turbines; a regulated utility balances the area, buys the energy and sells it to customers; and the state commission reviews what those customers pay [10]. The contract itself is not in this release. Only the plant, its owner, its operator and its balancing authority are.

Rattlesnake Flat on the generation map ↗(opens the atlas in a new tab)

A cooperative that only sells

Explore Orcas Power & Light Coop ↗

Orcas Power & Light Coop serves the San Juan Islands. It is a member-owned non-profit whose member-owners elect a seven-member board that sets policy and rates, and it buys its power from the Bonneville Power Administration as a full-requirements utility [26].

It owns no generation and operates none, and the atlas says so rather than filling the gap with a zero. Owned capacity reads Not applicable and operated capacity reads Not reported. Its retail sales are published on its organization page, from the annual industry survey [3].

Many organizations in this release look like that: a retail seller with no plants, buying from a marketer under a long-term contract. The preference for public bodies and cooperatives written into federal law [8] is a large part of why so many Northwest retail sellers buy from BPA rather than build.

Wind plants reporting to Avista's balancing authority ↗(opens the atlas in a new tab)

Reading the roles on the map

Every plant page names its operator, lists its owners with the megawatts each holds, and states the balancing authority it reports to. Every organization page carries its roles — owner, operator, retail seller — with owned and operated capacity, and, where it sells, retail sales by state and customer class. Every balancing authority page lists the plants that report to it.

In the atlas, search finds organizations and balancing authorities as well as plants, and selecting one filters the map. Filtering by an organization shows what that organization owns or operates. Filtering by a balancing authority shows what reports to it. The two sets rarely match, and that mismatch is the subject of this note.

Three habits make the rest readable. Read "operator" as who runs it, never as who owns it. Read a balancing authority as an accounting area, never as a service territory or a wire. And read a role that does not apply as missing rather than as zero.

Regulators are not on the map, but they are what makes two identical dams behave differently. Siting in Washington can run through the state council, which recommends and leaves the decision to the governor [16]. Regional planning sits with the Northwest Power and Conservation Council, which writes the power plan and whose fish and wildlife program guides BPA's project funding [17]. Neither of them owns, runs, balances or sells anything.

Washington plants and service areas ↗(opens the atlas in a new tab)

What this note does not claim

No contract appears here. The release carries owners, operators, balancing authorities and retail sales. It does not carry the power sales agreements, net billing arrangements or preference contracts that decide where the energy goes, and it does not describe what any utility's retail supply is made of. Money is absent too: no rates, no tariffs, no rate-case outcomes.

Nothing traces a household to a plant. A balancing authority is not a wire. A service territory is approximate geography, not a supply relationship. Ownership is not delivery. Where a role does not apply, the number stays missing rather than becoming zero.

The decision bodies named here are described from their own published statements of what they decide. The atlas does not yet model dockets, filings or determinations, and nothing on this page says what any of them will decide next.