The enclosure on a water heater, furnace, or boiler.

A structural, load-carrying building member with an open web system that supports floors and roofs utilizing wood or specific steels and is designed as a simple span member.

A metric unit of energy or work; the energy produced by a force of one Newton operating through a distance of one meter; 1 Joule per second equals 1 Watt or 0.737 foot-pounds; 1 Btu equals 1,055 Joules.

The rate of heat production by a steady current in any part of an electrical circuit that is proportional to the resistance and to the square of the current, or, the internal energy of an ideal gas depends only on its temperature.

A region of transition between semiconductor layers, such as a p/n junction, which goes from a region that has a high concentration of acceptors (p-type) to one that has a high concentration of donors (n-type).

A type of turbine that that has two blades whose pitch is adjustable. The turbine may have gates to control the angle of the fluid flow into the blades.

A type of heating fuel derived by refining crude oil that has a boiling range at atmospheric pressure from 400 degrees to 550 degrees F.

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

A standard unit of electrical power equal to one thousand watts, or to the energy consumption at a rate of 1000 Joules per second.

A unit or measure of electricity supply or consumption of 1,000 Watts over the period of one hour; equivalent to 3,412 Btu.

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

A wall usually about 3 to 4 feet high located that is placed in the attic of a home, anchored with plates between the attic floor joists and the roof joist. Sheathing can be attached to these walls to enclose an attic space.

In wastewater treatment or livestock facilities, a shallow pond used to store wastewater where sunlight and biological activity decompose the waste.

A light source composed of a metal base, a glass tube filled with an inert gas or a vapor, and base pins to attach to a fixture.

Features and vegetation on the outside of or surrounding a building for aesthetics and energy conservation.

A unit or measure of solar radiation; 1 calorie per square meter or 3.69 Btu per square foot.

The load created by moisture in the air, including from outside air infiltration and that from indoor sources such as occupants, plants, cooking, showering, etc.

The change in heat content that occurs with a change in phase and without change in temperature.

The quantity of heat produced to change a unit weight of a liquid to vapor with no change in temperature.

The regular periodic arrangement of atoms or molecules in a crystal of semiconductor material.