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.
The mechanism for choosing the lowest cost energy option that meets energy needs, which gives cheaper renewable energy and battery storage an edge.
Measurement used to calculate how much an energy resource–such as a wind farm or solar array–contributes to the overall reliability of the grid. It assesses the resource’s ability to meet electricity demand, particularly during peak usage periods, and is especially useful for variable renewable energy sources whose output depends on factors like weather conditions.
Measures that reduce electricity use in a home or business. These measures include replacing inefficient heating and air conditioners with heat pumps, adding attic insulation, and sealing ducts and foundation, walls, roof, windows, and doors of buildings. It also includes replacing energy-intensive appliances with more efficient ones. These measures can provide energy savings, improve comfort, and increase property values.
Connecting new generation to the grid with minimal transmission upgrades and managing impacts through operational strategies rather than extensive upfront infrastructure investments. This approach, often referred to as “connect and manage,” prioritizes adding generation capacity quickly while relying on the grid operator to manage any resulting operational constraints. It requires new resources to risk curtailment (where the generator is asked to stop supplying power to the grid when supply is too high). The process has allowed Texas’ ERCOT to connect record numbers of new clean projects in the last several years significantly faster than other regions.
The Electric Reliability Council of Texas serves as an independent system operator (ISO), managing the flow of electrical power over transmission infrastructure in the state of Texas.
A combination of automated and manual controls grid operators adjust to maintain grid reliability by ensuring a balance between supply (generation) and demand (load). They generally consist of three main aspects:
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
Wind turbines erected in bodies of water that harness the power of wind, converting it into electricity that is then transmitted to the mainland to power homes and businesses. Offshore wind farms are considered a renewable energy source.
The real-time balancing of energy supply and demand to maintain frequency and voltage within safe operating limits. It is the shorter-term dimension of reliability and requires regular monitoring and control of the entire grid. It includes the ability to quickly respond to sudden changes, like the loss of a major power plant or transmission line, and to handle normal variations in supply and demand.
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.
