The heat absorbed or released when a substance undergoes a change in temperature.

A heat storage system that uses a heat storage medium, and where the additional or removal of heat results in a change in temperature.

A configuration of an electrical circuit in which the positive lead is connected to the negative lead of another energy producing, conducting, or consuming device. The voltages of each device are additive, whereas the current is not.

A way of joining photovoltaic cells by connecting positive leads to negative leads; such a configuration increases the voltage.

Parasitic resistance to current flow in a cell due to mechanisms such as resistance from the bulk of the semiconductor material, metallic contacts, and interconnections.

A thermostat that can be set to automatically lower temperatures in an unoccupied house and raise them again before the occupant returns.

A measure of window glazing performance that is the ratio of the total solar heat gain through a specific window to the total solar heat gain through a single sheet of double-strength glass under the same set of conditions; expressed as a number between 0 ...

A construction element used to cover the exterior of wall framing and roof trusses.

An electric current taking a shorter or different path than intended.

The current flowing freely through an external circuit that has no load or resistance; the maximum current possible.

An interior or exterior movable panel that operates on hinges or slides into place, used to protect windows or provide privacy.

A construction element applied to the outermost surface of an exterior wall.

The sum of sensible heat and latent heat in a substance above a base temperature, typically 32 degrees Fahrenheit.

A chemical element, of atomic number 14, that is semi-metallic, and an excellent semiconductor material used in solar photovoltaic devices; commonly found in sand.

A technique for insulating and sealing exterior walls that reduces vapor diffusion through air leakage points by installing pre-cut blocks of rigid foam insulation over floor joists, sheet subfloor, and top plates before drywall is installed.

The type of alternative current generated by alternating current generators, rotary inverters, and solid-state inverters.

One layer of glass in a window frame. It has very little insulating value (R-1) and provides only a thin barrier to the outside and can account for considerable heat loss and gain.

In reference to solar photovoltaic devices, a material that is composed of a single crystal or a few large crystals.

A generator with a single armature coil, which may have many turns and the alternating current output consists of a succession of cycles.

The process of designing a solar system to meet a specified load given the solar resource and the nominal or rated energy output of the solar energy collection or conversion device.