EPA

Term Term Definition Options Unit of Measure
AC to AC An external ac-ac power supply is an EPS designed to convert line voltage ac input into lower voltage ac output. View N/A
AC to DC An external ac-dc power supply is an EPS designed to convert line voltage ac input into lower voltage dc output. View N/A
Accumulated nonactive energy The energy, in watt-hours (Wh), consumed by the battery charger in battery maintenance and standby modes of operation over a period of time. A standard 48-hour period is used for evaluation, consisting of 36 hours of maintenance mode operation followed by 12 hours of standby mode operation. View n/a
Anaerobic biodigester An anaerobic biodigester, contains methane, a natural by-product of anaerobic digestion of landfill refuse, sewage, and other products, which can be converted into electricity through conventional combustion processes. Equipping landfills and other facility premises (e.g., wastewater and manure treatment facilities) to capture biogas provides a source of on-site generation from a byproduct that would otherwise be wasted. View N/A
Battery energy The energy, in watt-hours (Wh), that may be delivered by the battery under specified discharge conditions. Battery energy is measured at a constant current discharge rate of 0.2 C, beginning with a fully charged battery and ending at the manufacturer specified cutoff voltage. View n/a
Bypass Equipment operating the load supplied via the Bypass only. View N/A
Combined energy factor Combined Energy Factor (CEF) is the energy performance metric for clothes dryers; the higher the CEF the more efficient the clothes dryer. CEF is the quotient of the test load size, 8.45 lbs for standard dryers and 3 lbs for compact dryers, C, divided by the sum of the machine electric energy use during standby and operational cycles. The equation is shown here: CEF = C (lbs) / (Eon + Estandby). The units are pounds per kWh, the higher the value, the more efficient the clothes dryer is. View n/a
Cool roof A cool roof reduces roof temperature with a high solar reflectance (or albedo) material that helps to reflect sunlight and heat away from a building. View N/A
Emissions Value

Emissions that result in gases that trap heat in the atmosphere.

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Energy factor A factor is used to compare the relative efficiency of water heaters, dishwashers, clothes washers, and clothes dryers. Energy Factor (EF) is the quotient of the capacity equipment divided by the sum of the equipment electrical energy for mechanical operation or standby, and the water heating energy. The units are volume (or weight) per energy per cycle. For dishwashers, the EF is the reciprocal of the sum of energy per cycle, and expressed in cycles per kWh. The higher the EF value means a more efficient equipment. It is the ENERGY STAR energy performance metric. This factor may vary based on equipment features such as water heating boosters or truncated cycles. The federal EnergyGuide label on equipment shows the annual energy consumption and cost, which use the energy factor. The EF does not appear on the EnergyGuide label. Unlike annual energy use, the EF does not take into account the estimated annual energy use in standby mode. The energy factor for a dehumidifier is calculated by dividing the water removed from the air by the energy consumed, measured in liters per kilowatt hour (L/kWh). View n/a
External Power Supply Mode

Designed to convert line voltage ac input into lower voltage ac or dc output, convert to only one output voltage at a time, contained in a separate physical enclosure from the end-use product, and does not have batteries or battery packs that physically attach directly (including those that are removable) to the power supply unit.

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Idle energy rate Idle energy rate represents the total idle energy consumed by the machine including all tank heaters) and controls, or while maintaining at a stabilized operating condition or temperature such as a thermostat(s) set point during the time period specified. Booster heater (internal or external) energy consumption should not be included. It's measured while equipment is enclosed. Also called standby energy rate. For cooking equipment, the purposes of the idle rate can be normalized based on the area of the (bottom) cooking surface. View n/a
Low voltage A low voltage model is an external power supply with a nameplate output voltage likely less than 6 volts and a nameplate output current greater than or equal to 550 milliamps. View N/A
Luminance

The photometric measure of the luminous intensity per unit area of light travelling in a given direction, expressed in candelas per square meter (cd/m2). 

View cd/m2
Nameplate input power The nameplate input power is either (a) the input power marked on the nameplate (watts), or (b) where only nameplate input voltage and current ranges are provided, the highest value achieved by multiplying a nameplate input voltage limit and its corresponding current limit (Volt-Amperes). View n/a
No load The condition in which the input of a power supply is connected to an ac source consistent with the power supplyÕs nameplate ac voltage, but the output is not connected to a product or any other load. View N/A
Nominal voltage Industry standard cell voltage multiplied by the number of cells in the battery pack. Nominal Battery Voltage is typically listed on battery packaging. View n/a
Normal Stable mode: a) Power source connected. b) The energy storage system remains charged or is under recharge. c) The load is within rating of equipment. d) The Bypass is available and within specified tolerances (if applicable). View N/A
Power usage effectiveness PUE is a measure of data center infrastructure efficiency, representing the amount of energy that is needed per unit delivered to IT equipment. It is computed as the total annual source energy divided by the annual IT source energy. View N/A
Radon Zone

The EPA Radon Zone

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Rated voltage The equipment's nameplate rated voltage is tested at standard testing conditions and indicates the voltage at which the equipment is designed to work. View n/a
Stored energy Stable mode: a)Power source is disconnected. b) All power is derived from the energy storage system. In the case of a DRUPS, from the integrated Diesel engine or a combination of both. c) The load is within rating of equipment. View N/A
Turbine Turbines generate electricity from mechanical energy exerted by a renewable resource, such as wind, or steam pressure from fuel burning. The mechanical energy creates a high-speed rotation that turns an electrical generator to produce electricity. View N/A
Water treatment Premises with operating water treatment plants including pumping stations, aqueducts, and/or distribution mains. View N/A
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