The minimum amount of electricity that a utility must provide to meet the consistent, ongoing needs of its customers. Historically, this steady demand was met by large power plants (like coal or nuclear) that ran continuously. Today, with more renewable energy, this minimum demand can be met by a flexible mix of various power sources, rather than relying solely on specific “baseload plants”.
A technology that stores electrical energy in rechargeable batteries for later use. Batteries help stabilize the grid, manage energy demand, and increase the use of renewable energy.
Any energy resource that provides energy directly to a home or business without passing through a utility company’s meter. Examples include rooftop solar and microgrids.
California ISO
The maximum amount of power an energy source can physically produce (measured in megawatts/MW), or when referring to an electrical grid, the total amount of electricity that power plants connected to the grid are capable of producing. It’s essentially the total potential output of all the electricity sources, like coal, nuclear, hydro, wind, and solar plants. Meanwhile, energy is the actual output of a source over a particular time period.
Generally, participants submit sealed bids to offer capacity at specific prices. The auction ends when the total capacity offered matches the region’s needs, and a single clearing price is set for all commitments.
An energy source that generates electricity with zero- or extremely low-carbon emissions, and can do so when needed, regardless of weather conditions. They include enhanced geothermal energy and advanced nuclear technologies. They also can include solar or wind paired with battery storage to provide on-demand power supply regardless of weather conditions or time of day.
Refers to a regulatory approach for connecting new power generators to the electrical grid, notably used in Texas (ERCOT). This approach allows new generators to connect expeditiously with minimal upfront transmission upgrades. However, the grid operator retains the right to curtail their output if transmission constraints arise. This contrasts with approaches where developers pay for upgrades prior to connection. (see Energy-only interconnection approaches)
An accelerated stakeholder process used in PJM Interconnection to resolve urgent, contentious, and time-sensitive issues that cannot be resolved through the normal stakeholder process. The process involves several stages of discussion and proposal development, culminating in a submission to the Federal Energy Regulatory Commission (FERC) for approval. The CIFP process has been used in recent years to discuss large load additions (2025) and resource adequacy (2023).
Historically refers to industrial facilities with high electrical demand. They had long interconnection timelines that allowed for more study time under traditional planning processes. Currently, emerging large loads include cryptocurrency mining, data centers (conventional and artificial intelligence), oil field loads, and hydrogen production facilities. Many have a shorter timeline to interconnect (months vs. years) to the grid. In addition to these rapid timelines, some emerging large loads introduce new challenges to grid operators like rapid demand fluctuations and increased voltage sensitivity.
The amount of power or electricity consumed by a device or system at a given time. It’s the demand placed on an energy source, like a power grid or a battery, by the connected electrical equipment.
The increase in the demand for electricity over time. It signifies the rising need for power from various sectors, including residential, commercial, and industrial, and can be driven by factors like population increases, economic development, and the adoption of new technologies like electric vehicles and data centers.
A controlled process where a utility company reduces or shuts off power supply to certain areas or customers to balance demand with available supply, preventing a complete system failure. It’s a last-resort measure to maintain grid stability when demand exceeds supply or when there are issues with power generation or transmission.
A way for wholesale electric energy prices to reflect the value of electric energy at different locations, accounting for the patterns of load, generation, and the physical limits of the transmission system.
Analysis is typically performed on a system to determine the amount of capacity that needs to be installed to meet the desired reliability target, commonly expressed as an expected value, or LOLE of 0.1 days/year.
Midcontinent Independent System Operator, serves northern Midwest, southeast, and parts of Canada
Power that does not perform useful work but is used to establish and maintain electromagnetic fields that are needed to generate, transmit, and convert electric power in the alternating current network. A shortage of reactive power can cause voltage to decline. (See also: voltage support)
A characteristic of the whole electricity system to describe its ability to consistently deliver electricity to consumers without interruption, even through grid disturbances. Reliability comes down to having sufficient generating resources to meet demand and a functional operational grid system.
An agreement initiated by an RTO or ISO with a power plant, keeping it in operation temporarily for reliability purposes.
The ability of the grid to ride through extreme events, recover quickly, and support other critical systems (e.g., transportation, health care, public safety etc.).
An assessment of whether the current or projected resource mix is sufficient to meet capacity and energy needs for a particular grid. The resource mix includes all resources able to provide capacity and energy to the system. Adequacy assessments are used to identify potential shortfalls in the availability of resources across different time frames; from long-term planning (5 to 20+ years) to seasonal and day-ahead assessments.
