A house built using passive solar design techniques.

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

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

A pole used to assist in raising a tower.

These lights use an electrically heated filament to produce light in a vacuum or inert gas-filled bulb.

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

A mainly flat surface for transmitting radiant energy.

Any device (or plant) that follows the sun's apparent movement across the sky.

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

The ratio of the percentage change in the quantity of a good or service demanded to the percentage change in the price.

A hydrocarbon gas obtained from underground sources, often in association with petroleum and coal deposits. It generally contains a high percentage of methane, varying amounts of ethane, and inert gases; used as a heating fuel.

A salt, sodium sulfate decahydrate, that melts at 90 degrees Fahrenheit; a component of eutetic salts that can be used for storing heat.

A configuration of an electrical circuit in which the voltage is the same across the terminals. The positive reference direction for each resistor current is down through the resistor with the same voltage across each resistor.

A type of water heater that circulates water through a heat exchanger in a boiler. The heated water then flows into an insulated storage tank.

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 building energy auditing technique for locating areas of low insulation in a building envelope by means of a thermographic scanner.

The area of glass that fits in the window frame.

A type of water heater that has no storage tank thus eliminating storage tank standby losses. Cold water travels through a pipe into the unit, and either a gas burner or an electric element heats the water only when needed.

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

This is a national organization dedicated to representing the interests of cooperative electric utilities and the consumers they serve. Members come from the 46 states that have an electric distribution cooperative.