A mainly flat surface for transmitting radiant energy.

A drag-type wind machine that can react to wind from any direction.

A type of lamp having a lens of heavy durable glass that focuses the light. They have longer lifetimes with less lumen depreciation than standard incandescents.

A solar energy conversion device that has a bowl shaped dish covered with a highly reflective surface that tracks the sun and concentrates sunlight on a fixed absorber, thereby achieving high temperatures, for process heating or to operate a heat (Stirlin ...

A solar energy conversion device that uses a trough covered with a highly reflective surface to focus sunlight onto a linear absorber containing a working fluid that can be used for medium temperature space or process heat or to operate a steam turbine fo ...

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 way of joining photovoltaic cells or modules by connecting positive leads together and negative leads together; such a configuration increases the current, but not the voltage.

The fine liquid or solid particles contained in combustion gases. The quantity and size of particulates emitted by cars, power and industrial plants, wood stoves, etc are regulated by the U.S. Environmental Protection Agency.

A building design that uses structural elements of a building to heat and cool a building, without the use of mechanical equipment, which requires careful consideration of the local climate and solar energy resource, building orientation, and landscape fe ...

A solar water or space-heating system in which solar energy is collected, and/or moved by natural convection without using pumps or fans. Passive systems are typically integral collector/storage (ICS; or batch collectors) or thermosyphon systems. The majo ...

A house built using passive solar design techniques.

To allow or augment the natural movement of cooler air from exterior, shaded areas of a building through or around a building.

The amount of time required for positive cash flows to equal the total investment costs.

The process of implementing measures to reduce peak power demands on a system.

The maximum energy demand or load in a specified time period.

Power generated by a utility unit that operates at a very low capacity factor; generally used to meet short-lived and variable high demand periods.

The process of moving existing loads to off-peak periods.

A unit used to rate the performance of a solar photovoltaic (PV) cells, modules, or arrays; the maximum nominal output of a PV device, in Watts (Wp) under standardized test conditions, usually 1000 Watts per square meter of sunlight with other conditions, ...

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

Power generation equipment or system capacity to meet peak power demands.