Restrictions on the use of a property.

The unoccupied, and usually unfinished and unconditioned space between the floor, foundation walls, and the slab or ground of a building.

A liquid byproduct of wood combustion (or distillation) that condenses on the internal surfaces of vents and chimneys, which if not removed regularly, can corrode the surfaces and fuel a chimney fire.

The highest possible pressure in a fuel-air mixture before spontaneous ignition occurs.

In reference to wind energy, for any given instant, the power available in the wind is proportional to the cube of the wind velocity; when wind speed doubles, the power availability increases eight times.

A unit of volume equal to 1 cubic foot at a pressure base of 14.73 pounds standard per square inch absolute and a temperature base of 60 degrees Fahrenheit.

The flow of electrical energy (electricity) in a conductor, measured in amperes.

The value or purchasing power of a dollar that has not been reduced to a common basis of constant purchasing power, but instead reflects anticipated future inflation; when used in computations the assumed inflation rate must be stated.

An amount to be paid for energy periodically by a customer without regard to demand or energy consumption.

Categories of energy consumers, as defined by consumption or demand levels, patterns, and conditions, and generally included residential, commercial, industrial, agricultural.

The lowest wind speed at which a wind turbine begins producing useable power.

The highest wind speed at which a wind turbine stops producing power.

In alternating current, the current goes from zero potential or voltage to a maximum in one direction, back to zero, and then to a maximum potential or voltage in the other direction. The number of complete cycles per second determines the current frequen ...

The loss of heat as the water circulates through a water heater tank and inlet and outlet pipes.

A furnace/combustion chamber in which finely ground fuel is blown in spirals in the combustion chamber to maximize combustion efficiency.

A method of growing large size, high quality semiconductor crystal by slowly lifting a seed crystal from a molten bath of the material under careful cooling conditions.

A structure for impeding and controlling the flow of water in a water course, and which increases the water elevation to create the hydraulic head. The reservoir creates, in effect, stored energy.

A movable plate used to control air flow; in a wood stove or fireplace, used to control the amount and direction of air going to the fire.

A type of vertical-axis wind machine that has long, thin blades in the shape of loops connected to the top and bottom of the axle; often called an "eggbeater windmill."

The use of direct, diffuse, or reflected sunlight to provide supplemental lighting for building interiors.