Thermosyphon systems use a separate storage tank located above the collector. Liquid warmed in the collector rises naturally above the collector, where it is kept until it is needed. The liquid can be either water or a glycol solution. If the fluid is wat ...

A layer of semiconductor material, such as copper indium diselenide or gallium arsenide, a few microns or less in thickness, used to make solar photovoltaic cells.

Alternating current in which three separate pulses are present, identical in frequency and voltage, but separated 120 degrees in phase.

The power available from the rise and fall of ocean tides. A tidal power plant works on the principal of a dam or barrage that captures water in a basin at the peak of a tidal flow, then directs the water through a hydroelectric turbine as the tide ebbs.

The angle at which a solar collector or module is set to face the sun relative to a horizontal position. The tilt angle can be set or adjusted to maximize seasonal or annual energy collection.

A device that can be set to automatically turn appliances (lights) off and on at set times.

This device can automatically turn the heater off at night and on in the morning.

In reference to a wind energy conversion device's blades, the difference between the rotational speed of the tip of the blade and the actual velocity of the wind.

A unit of air cooling capacity; 12,000 Btu per hour.

A means to increase the thermal efficiency of a steam electric generating system by increasing temperatures and interposing a device, such as a gas turbine, between the heat source and the conventional steam-turbine generator to convert some of the additi ...

The turning or twisting force generated by an electrical motor in order for it to operate.

The measure of closeness in shape between a waveform and it's fundamental component.

The sum of the sensible and latent heat in a substance or fluid above a base point, usually 32 degrees Fahrenheit.

The total radiation incident on a specific surface area over a time interval.

The trapping of light by refraction and reflection at critical angles inside a semiconductor device so that it cannot escape the device and must be eventually absorbed by the semiconductor.

A solar energy array that follows the path of the sun to maximize the solar radiation incident on the PV surface. The two most common orientations are (1) one axis where the array tracks the sun east to west and (2) two-axis tracking where the array point ...

The part of a wind energy conversion device blade, or airfoil, that is the last to contact the wind.

An electromagnetic device that changes the voltage of alternating current electricity. It consists of an induction coil having a primary and secondary winding and a closed iron core.

The process of sending or moving electricity from one point to another; usually defines that part of an electric utility's electric power lines from the power plant buss to the last transformer before the customer's connection.

The losses that result from inherent resistance in electrical conductors and transformation inefficiencies in distribution transformers in a transmission and distribution network.