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

These are state government agencies responsible for the regulation of public utilities within a state or region. A state legislature oversees the PUC by reviewing changes to utility laws, rules and regulations and approving the PUC's budget. The commissio ...

A slender threadlike spike of pure crystalline material, such as silicon.

A combustion heating appliance that vents the combustion by-products directly into the heated space. The latest models have oxygen-sensors that shut off the unit when the oxygen level in the room falls below a safe level.

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 ...

The area between the layers of glazing (panes) of a window.

An air distribution outlet, typically located in the ceiling, which mixes conditioned air with room air.

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 ...

A component of a hydropower plant; a pipe that delivers water to the turbine.

That portion of supply air that is drawn from outside, plus any recirculated air that has been treated to maintain a desired air quality.

A unit of apparent power, equal to 1,000 volt-amperes; the mathematical product of the volts and amperes in an electrical circuit.

An apparatus for converting the energy available in the wind to mechanical energy that can be used to power machinery (grain mills, water pumps) and to operate an electrical generator.

The conversion of the complex carbohydrates in organic material into energy.

A pump for circulating the heat transfer fluid in a hydronic heating system.

The weight of a material per unit of volume compared to the weight of the same volume of water.

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 material used to seal areas of potential air leakage into or out of a building envelope.

Energy available as a result of motion that varies directly in proportion to an object's mass and the square of its velocity.

A method of preventing oxidation of the exposed metal in structures by imposing between the structure and the ground a small electrical voltage.

To disconnect a transmission and/or distribution line; a power line that is not carrying a current; to open a circuit.