In battery technology, a concentration cell is a limited form of a galvanic cell that has two equivalent half-cells of the same composition differing only in concentrations.

A solar power system that utilises mirrors or lenses to concentrate sunlight onto a reciever where it can be converted into heat energy to drive a steam turbine.

Computer simulation is the process of mathematical modelling, performed on a computer, which is designed to predict the behaviour of, or the outcome of, a real-world or physical system.

Computational fluid dynamics is a branch of fluid mechanics that uses numerical analysis and data structures to analyze and solve problems that involve fluid flows.

A compressor stall is a local disruption of the airflow in the compressor of a gas turbine or turbocharger.

The central component of a heat pump system.

A compressor is a mechanical device that increases the pressure of a gas by reducing its volume.

Compressive strength or compression strength is the capacity of a material or structure to withstand loads tending to reduce size, as opposed to Tensile strength which withstands loads tending to elongate.

The compression ratio is the ratio between the volume of the cylinder and combustion chamber in an internal combustion engine at their maximum and minimum values.

An internal cumbustion engine where air is drawn into a cylinder and in the compression cycle fuel injected into the cylinder causing the mixture to detonate.

In mechanics, compression is the application of balanced inward ("pushing") forces to different points on a material or structure, that is, forces with no net sum or torque directed so as to reduce its size in one or more directions.

In thermodynamics and fluid mechanics, the compressibility (also known as the coefficient of compressibility or, if the temperature is held constant, the isothermal compressibility) is a measure of the relative volume change of a fluid or solid as a response to a pressure (or mean stress) change.

Compressed-air energy storage (CAES) is a way to store energy generated at one time for use at another time using compressed air.

A composite material is a material which is produced from two or more constituent materials.

A compliant tower is a fixed rig structure normally used for the offshore production of oil or gas.

In business, a competitive advantage is the attribute that allows an organization to outperform its competitors. A competitive advantage may include access to natural resources, such as high-grade ores or a low-cost power source, highly skilled labor, geographic location, high entry barriers, and access to new technology.

A compact linear Fresnel reflector is a specific type of linear Fresnel reflector technology.

A commutator is a rotary electrical switch in certain types of electric motors and electrical generators that periodically reverses the current direction between the rotor and the external circuit.

Community wind projects are locally owned by farmers, investors, businesses, schools, utilities, or other public or private entities who utilize wind energy to support and reduce energy costs to the local community.

To bring a facility or machine into service, to ensure that all components function as designed and intended.