Also known as real or true power, is the portion of electrical power that does useful work in a circuit, such as generating heat, light, or mechanical energy. (see related: reactive power)
A preliminary document used by government agencies to solicit public feedback on potential new rules or reforms before they are officially proposed. It outlines initial ideas, asks specific questions, and serves as the first step in a larger regulatory process. The acronym is frequently used by the Federal Energy Regulatory Commission (FERC). It precedes a formal Notice of Proposed Rulemaking (NOPR) and allows agencies to gauge public opinion and gather information to develop a more informed proposal.
(see also: Essential reliability services) – Supplementary services essential for maintaining the reliable operation and stability of the electrical grid beyond the basic generation and transmission of energy. They are “behind-the-scenes” services that include real-time balancing of electricity supply and demand, maintaining voltage levels, and providing the capability to restart the grid after a widespread outage (black start).
Is an automated system that continuously monitors the electrical network and adjusts the power output of multiple generators. Its primary functions are to maintain system frequency (60 Hz in United States), in response to changes in the power demand, or load.
These incentivize customers to reduce, increase, or shift their electricity consumption in response to price spikes or grid reliability signals. Most programs encourage utility customers primarily through price incentives to shift electricity consumption from hours of high demand (relative to energy supply) to hours when energy supply is plentiful (relative to demand).
These encompass strategies and programs designed to influence electricity consumption patterns on the customer side of the meter. These initiatives aim to moderate electricity demand through methods such as financial incentives for energy conservation and energy efficiency measures, like improved insulation or the adoption of energy-efficient appliances.
Refers to electricity generation resources that power grid operators can control and adjust on demand to meet changing electricity needs. These include nuclear, hydropower, battery storage, and thermal power plants.
Small-scale energy generation and storage technologies located near the point where the energy is used, rather than at a centralized power plant. These resources–such as solar microgrids, rooftop solar, and battery storage–can be used to enhance or replace traditional energy sources and can operate independently or be connected to the main grid.
Refers to any unwanted or unplanned electrical event that interferes with the normal operation of the electrical grid. These can manifest in power outages, surges, and other events, and can originate from various sources within the electrical grid, such as loss of a large generating unit or another grid asset, such as a transmission line or transformer.
The ability of a piece of electrical equipment to stay connected to the grid through a short-term disturbance, thus helping keep the grid stable through the event. Inverter-based resources, such as photovoltaic solar arrays, wind turbines, and battery storage, can provide disturbance ride-through services, but require specific design of their control system to do so.
In energy regulation, it is a formal proceeding or official record initiated by a regulatory body (such as a Public Utilities Commission or the Federal Energy Regulatory Commission (FERC)) to address a specific issue or project. It serves as a repository for all submitted documents, evidence, and public comments.
A visual representation of how solar power generation impacts the daily electricity demand curve, particularly in regions with high solar adoption like California. It depicts a dip in net electricity demand during midday due to solar generation, followed by a steep increase in the evening as solar output decreases and demand peaks.
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.
(see also: ISO) – A non-profit organization that manages the electricity transmission system in a specific region, ensuring reliable and efficient electricity delivery. RTOs operate the high-voltage electricity grid, facilitating the movement of power from generating plants to substations and ultimately to consumers. They also oversee competitive wholesale electricity markets.
A type of power station in which the heat energy generated from various fuel sources (e.g., coal, natural gas, nuclear fuel, etc.) is converted to electrical energy.
The maximum amount of electrical power that can be reliably moved from one geographic region of the power grid to another, essentially indicating the ability of the transmission lines connecting those regions to transport electricity between them without causing instability or exceeding safety limits. It’s a crucial concept for ensuring the safe and efficient operation of the power system, particularly in the context of electricity markets and grid planning.
