The value or purchasing power of a dollar in a specified year carried forward or backward.

Wind turbines that operate at a constant rotor revolutions per minute (RPM) and are optimized for energy capture at a given rotor diameter at a particular speed in the wind power curve.

The part of an energy utility's charge based on actual energy consumed by the customer; the product of the kilowatt-hour rate and the total kilowatt-hours consumed.

The resistance between metallic contacts and the semiconductor.

A steady-state fermentation process.

The difference between the brightness of an object compared to that of its immediate background.

The transfer of heat by means of air currents.

The fossil fuels: coal, oil, and natural gas.

This type of heat pump is known as an air-to air system.

The amount of energy produced as a percentage of the amount of energy consumed.

A device for transforming the quality and quantity of electrical energy; also an inverter.

The quantity of heat that a cooling appliance is capable of removing from a room in one hour.

A value used to estimate interior air cooling requirements (load) calculated as the number of degrees per day (over a specified period) that the daily average temperature is above 65 degrees Fahrenheit (or some other, specified base temperature). The dail ...

That amount of cooling energy to be supplied (or heat and humidity removed) based on the sensible and latent loads.

A body of water used to cool the water that is circulated in an electric power plant.

A structure used to cool power plant water; water is pumped to the top of the tubular tower and sprayed out into the center, and is cooled by evaporation as it falls, and then is either recycled within the plant or is discharged.

The potentially useful byproducts of ethanol fermentation process.

A stack of wood 4 feet by 4 feet by 8 feet.

A unit for the quantity of electricity transported in 1 second by a current of 1 ampere.

A heat exchanger in which two fluids flow in opposite directions for transfer heat energy from one to the other.