Referring to alterations in the environment due to the presence or activities of humans.

A type of hydroturbine in which the entire generator is mounted inside the water passageway as an integral unit with the turbine. These installations can offer significant reductions in the size of the powerhouse.

The purpose for which useful energy or work is consumed.

A mechanical device used for air circulation and to provide cooling.

A device that cuts off the flow of hot or cold air to or from a room as controlled by a thermostat.

A condition that results from an imbalance between the number of protons and the number of electrons in a substance.

Biomass converted directly to energy or converted to liquid or gaseous fuels such as ethanol, methanol, methane, and hydrogen.

The negative pole or electrode of an electrolytic cell, vacuum tube, etc., where electrons enter (current leaves) the system; the opposite of an anode.

The maximum load that a motor is capable of supplying.

A device that cools air by removing moisture from it.

A device that moves and/or circulates air and provides ventilation for a room or a building.

Consist of three main layers. The top layer is near ambient and has low salt content. The bottom layer is hot, typically 160 F to 212 F (71 C to 100 C), and is very salty. The important gradient zone separates these zones. The gradient zone acts as a tran ...

A measure of the heating requirements of a building expressed in Btu per degree-day.

Heat stored above room temperature (in a solar heating system).

A colorless, pungent, gas (NH3) that is extremely soluble in water, may be used as a refrigerant; a fixed nitrogen form suitable as fertilizer.

A popular term for "non-conventional" transportation fuels derived from natural gas (propane, compressed natural gas, methanol, etc.) or biomass materials (ethanol, methanol).

The amount of power a wind turbine can produce at its rated wind speed, e.g., 100 kW at 20 mph. The rated wind speed generally corresponds to the point at which the conversion efficiency is near its maximum. Because of the variability of the wind, the amo ...

Energy systems supply individual, or small-groups, of energy loads.

The total cost of production divided by the total quantity produced.

A building structural element that is built onto a building's exterior along the inner edges of all the windows, and extending from the ground to the eaves. Wingwalls help ventilate rooms that have only one exterior wall which leads to poor cross ventilat ...