A measure of the amount of energy lost during the generation, transmission, and distribution of electricity.

The process of using heat that is rejected in one part of a cycle for another function or in another part of the cycle.

A type of heating appliance similar to a fireplace, but much more efficient and clean burning. They are made of masonry and have long channels through which combustion gases give up their heat to the heavy mass of the stove, which releases the heat slowly ...

A device used to measure total incident solar radiation (direct beam, diffuse, and reflected radiation) per unit time per unit area.

A heating system that uses only outside air for combustion and vents combustion gases directly to the outdoors. These systems are less likely to backdraft and to negatively affect indoor air quality.

An electricity powered device that extracts available heat from one area (the heat source) and transfers it to another (the heat sink) to either heat or cool an interior space or to extract heat energy from a fluid.

A wood-burning appliance for space and/or water heating and/or cooking.

Energy produced by the conversion of biomass directly to heat or to a liquid or gas that can be converted to energy.

The addition of dopants to a semiconductor.

The ratio of fuel energy input as heat per unit of net work output; a measure of a power plant thermal efficiency, generally expressed as Btu per net kilowatt-hour.

Materials with various qualities that are applied to glass windows before installation. These coatings reduce radiant heat transfer through the window and also reflects outside heat and a portion of the incoming solar energy, thus reducing heat gain. The ...

This designates the resistance of a material to heat conduction. The greater the R-value the larger the number.

A measure of the efficiency of converting a fuel to energy and useful work; useful work and energy output divided by higher heating value of input fuel times 100 (for percent).

A gas or liquid used to move heat energy from one place to another; a refrigerant.

The maximum instantaneous wind speed (or velocity) that occurs within a specific period of time or interval.

In a given electrical circuit, the amount of current in amperes (i) is equal to the pressure in volts (V) divided by the resistance, in ohms (R).

One thousand kilowatt-hours or 1 million watt-hours.

One thousand kilowatts, or 1 million watts; standard measure of electric power plant generating capacity.

The rate of flow of the wind undisturbed by obstacles.

The rate of heat flow required to maintain a specific indoor temperature; usually measured in Btu per hour.