How Does That Work?

What you need to know about RTOs

OPPD is a member of the Southwest Power Pool (SPP), a regional transmission organization that comprises 109 utilities and transmission companies from Texas to North Dakota and the western part of Montana.

OPPD has been a member since 2009.

What do regional transmission organizations do? Read on.

What are regional transmission organizations?

Regional transmission organizations (RTOs) and independent system operators (ISOs) are the “air traffic controllers” of the electric power grid. They manage the power grid minute-by-minute, ensuring the grid’s safety and reliability when bad weather strikes and plants or transmission lines go down.

SPP is one of nine nonprofit RTOs/ISOs in North America.

RTOs and ISOs perform the same functions, but RTOs typically cover a larger geographic area and must meet certain additional Federal Energy Regulatory Commission (FERC) requirements, said Colin Sniff, OPPD’s Energy Regulatory Policy manager. ISOs typically cover individual states.

RTOs are also tasked with a greater responsibility for the transmission network, Sniff said. SPP works with members like OPPD to plan transmission projects across the region to make sure the transmission system remains robust and reliable.

Collaborating to keep the lights on

The nine RTOs formed a group called the ISO/RTO Council (IRC) in 2003. The group and its committees consist of representatives from each of the ISO/RTO members. The group collaborates “to match power generation instantaneously with demand to keep the lights on and ensure access to affordable, reliable and sustainable power via wholesale energy markets,” according to the IRC’s Emerging Technologies Task Force.

The utilities represented by the nine members provide power to two-thirds of the U.S. and more than half of Canada. The group has seven committees that cover areas like planning, regulatory and legislative issues, and markets, among others.

SPP, like the other eight RTOs, is mandated by FERC to ensure reliable supplies of power, adequate transmission infrastructure and competitive wholesale prices of electricity.

Utilities in areas without RTOs or ISOs are not able to economically utilize wholesale markets and reliable generation access and instead mainly rely on their own generation.

The members

The nine RTOs and ISOs in North America are:

Alberta Electric System Operator (AESO)

California ISO (CAISO)

Electric Reliability Council of Texas (ERCOT)

Independent Electric System Operator (of Ontario) (IESO)

ISO New England (ISONE)

Midcontinent ISO (MISO)

New York ISO (NYISO)

PJM Interconnection

Southwest Power Pool (SPP)