An electrochemical battery that uses lead and lead oxide for electrodes and sulfuric acid for the electrolyte.

The amount of useful energy produced by a system less the amount of energy required to produce the fuel.

The process of breaking down organic material; reduction of the net energy level and change in physical and chemical composition of organic material.

Energy supplied during periods of relatively high system demands as specified by the supplier.

The distance between similar points on successive waves.

The quantity of heat necessary to raise the temperature of a specific mass of a substance by one degree.

The coldest months of the year; months where average daily temperatures fall below 65 degrees Fahrenheit creating demand for indoor space heating.

A statement of the electric rate(s), terms, and conditions for electricity sale or supply.

The amount of solar radiation striking a surface per unit of time and area.

A description of how well people in a lighted space can see to do visual tasks and how visually comfortable they feel in that space.

The structural elements (walls, roof, floor, foundation) of a building that encloses conditioned space; the building shell.

Standardized weights or volumes for heating fuels.

A unit of pressure for a fluid, commonly used in water pumping and hydropower to express height a pump must lift water, or the distance water falls. Total head accounts for friction head losses, etc.

A coil of tungsten wire suspended in a vacuum or inert gas-filled bulb. When heated by electricity the tungsten "filament" glows.

The wind speed with 50 percent probability of occurring.

The amount of heat introduced to a space from all heat producing sources, such as building occupants, lights, appliances, and from the environment, mainly solar energy.

A registered trademark name for houses built with tires, aluminum cans, and earth.

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

A device that captures the heat from the exhaust air from a building and transfers it to the supply/fresh fresh air entering the building to preheat the air and increase overall heating efficiency.

The price paid for goods or services at the time of a transaction; a price that has not been adjusted to account for inflation.