In chemistry, a solution is a special type of homogeneous mixture composed of two or more substances.

Solubility is the property of a solid, liquid or gaseous chemical substance called solute to dissolve in a solid, liquid or gaseous solvent.

Solids control is a process used in drilling rigs which use drilling fluid.

A solid state relay is an electronic switching device that switches on or off when an external voltage (AC or DC) is applied across its control terminals.

Solid-state electronics means semiconductor electronics: electronic equipment using semiconductor devices such as transistors, diodes and integrated circuits. The term is also used for devices in which semiconductor electronics which have no moving parts replace devices with moving parts, such as the solid-state relay.

An electrochemical conversion device that produces electricity directly from oxidizing a fuel. Fuel cells are characterized by their electrolyte material such as the solid oxide fuel cell which has a solid oxide or ceramic electrolyte.

Solid fuel refers to various types of solid material that are used as fuel to produce energy and provide heating, usually released through combustion.

Solid earth refers to "the earth beneath our feet" or terra firma, the planet's solid surface and its interior.

Waste-to-energy is the process of generating energy in the form of electricity and/or heat from the primary treatment of waste, or the processing of waste into a fuel source.

Waste oil is defined as any petroleum-based or synthetic oil that, through contamination, has become unsuitable for its original purpose due to the presence of impurities or loss of original properties.

A generator that produces steam from the heat generated by an engines exhaust system.

Waste heat is heat that is produced by a machine, or other process that uses energy, as a byproduct of doing work.

Sometimes called battle of the currents, was a series of events surrounding the introduction of competing electric power transmission systems (AC and DC) in the late 1880s and early 1890s

A thin slice of semiconductor, such as a crystalline silicon (c-Si), used for the fabrication of integrated circuits and, in photovoltaics, to manufacture solar cells.

In continuum mechanics, vorticity is a pseudovector field that describes the local spinning motion of a continuum near some point (the tendency of something to rotate, as would be seen by an observer located at that point and traveling along with the flow.

A wake created due to the reduction of wind speed after it crosses a turbine blade.

A vortex generator is an aerodynamic device, consisting of a small vane usually attached to a lifting surface (or airfoil, such as an aircraft wing) or a rotor blade of a wind turbine.

In fluid dynamics, a vortex is a region in a fluid in which the flow revolves around an axis line, which may be straight or curved.

The heat capacity of a sample of the substance divided by the volume of the sample.

In physics and engineering, in particular fluid dynamics, the volumetric flow rate is the volume of fluid which passes per unit time; usually it is represented by the symbol Q.