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# AVERT - Glossary

Demand response programs: Demand response programs are incentive-based programs that encourage electric power customers to temporarily reduce their demand for power at certain times in exchange for a reduction in their electricity bills. Demand response programs may not always provide emission reduction benefits. For instance, some demand response programs relieve demand from the electric grid by replacing that generation with back-up generators that emit emissions. Using approaches, such as cycling down equipment to curtail electricity demand are the right type of demand response programs for AVERT.

Electric generating unit (EGU): The component of a power plant that produces electricity. Some power plants may have multiple EGUs on a single plant site. EGUs include facilities from electric utilities and independent power producers, and include all types of generating facilities (e.g. fossil, nuclear, hydro, and renewable).

Capacity: The maximum electric output an EGU can produce, commonly expressed in kilowatts (kW) or megawatts (MW).

Generation: The amount of electricity that an EGU can produce over a specific period of time, commonly expressed in kilowatt-hours (kWh) or megawatt-hours (MWh).

Capacity factor: The fraction of an EGU’s total available capacity that is utilized over a period of time, expressed as a fraction. For example, an EGU operating at 50% capacity factor produces half the amount of energy that it could have produced operating at full capacity over all hours.

Goodness of fit:  The goodness of fit of a statistical model describes how well the model fits a set of observed values. AVERT uses the R2 metric to describe goodness of fit, or how well dependent variables describe independent variables (i.e., how well the y-axis values describes the x-axis values) in the Signal-to-Noise Diagnostic, A set of random values that do not fit the observed data at all has an R2 value of zero (0), while perfectly matched data have an R2 value of one (1).

Hourly capacity factor: The fraction of an EGU’s total available capacity that is utilized in an hour.