The changing resource mix is creating significant concerns with the owners, operators, and regulators of the bulk power system (BPS), as the new resources do not behave in the same way as the legacy resources, and reliability may be impacted. Large rotating machines have historically provided energy, as well as essential reliability services such as inertia, to help the power system to recover from a frequency event, ramping capability to follow changing loads and voltage support. Many of the new resources either cannot provide these essential reliability services, or were not initially designed to provide them. They were designed to provide renewable energy to serve the load.

Changing Resource Mix

Rapidly changing resource mix and increased levels of renewable energy resources are among the most significant reliability challenges for the long-term planning and operation of the BPS.

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Huge growth in wind and solar power over the past decades are creating challenges and power system operators are responding.

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Essential Reliability Services

Essential reliability services (ERS) components must be available to support the bulk electric system.

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