The volume of a unit weight of a substance at a specific temperature and pressure.

As defined by the Comprehensive National Energy Act of 1992 (or the Energy Policy Act; EPAct): any organic matter from a plant which is planted for the exclusive purpose of being used to produce energy." This does not include wood or agricultural wastes o ...

Fuels formed in the ground from the remains of dead plants and animals. It takes millions of years to form fossil fuels. Oil, natural gas, and coal are fossil fuels.

ICS solar systems are also called "batch" or "breadbox" water heaters. They combine the collector and storage tank in one unit. The sun shining into the collector strikes the storage tank directly, heating the water. The large thermal mass of the water, p ...

A tubular material used to encase and protect one or more electrical conductors.

The outer casing of a window that sits in a designated opening of a structure and holds the window panes in place.

A solar energy collection device consisting of containers of water located on a roof that absorb solar energy during the day so that the heat can be used at night or that cools a building by evaporation at night.

A high-intensity discharge lamp type that uses mercury and several halide additives as light-producing elements. These lights have the best Color Rendition Index (CRI) of the High-Intensity Discharge lamps. They can be used for commercial interior lightin ...

A solid-state electrical device that converts light directly into direct current electricity of voltage-current characteristics that are a function of the characteristics of the light source and the materials in and design of the device. Solar photovoltai ...

A system where heat is supplied to areas of a building from a single appliance through a network of ducts or pipes.

A small groove scribed into the surface of a solar photovoltaic cell which is filled with metal for contacts.

A type of furnace in which fuel is spread, automatically or mechanically, across the furnace grate.

The flow rate in these systems is 1/8 to 1/5 the rate of most solar water heating systems. The low-flow systems take advantage of stratification in the storage tank and theoretically allows for the use of smaller diameter piping to and from the collector ...

Technologies that pertain to the generation of electricity.

The temperature that a system is designed to maintain (inside) or operate against (outside) under the most extreme conditions.

A column of gas at standard conditions of temperature and pressure (32 degrees Fahrenheit and one atmosphere).

The storage of compressed air in a container for use to operate a prime mover for electricity generation.

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.

A smokestack or flue for exhausting the products of combustion from a combustion appliance.

All the natural and living things around us. The earth, air, weather, plants, and animals all make up our environment.