English Glossary

Since 02.06.2017

Browse the glossary using this index

Special | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | ALL

Page:  1  2  3  (Next)





mode of energy transfer (e.g. heat, light) from a source to an object which does not require contact between source and object (i.e. the energy can be transmitted through a vacuum)

radiation heat transfer

Heat transfer via electromagnetic radiation. The only mode of heat transfer that can pass through a vacuum.

radioactive decay

Radioactive decay (also known as nuclear decay or radioactivity) is the process by which an unstable atomic nucleus loses energy (in terms of mass in its rest frame) by emitting radiation.


Weather measurement device with a radio transmitter connected to a balloon.

Rankine cycle

Thermodynamic cycle of a heat engine that converts heat into mechanical work. Used to predict the performance of steam turbine systems, such as steam-operated heat engines commonly found in thermal power generation plants.

rapid voltage changes

Voltage steps or other voltage variations (single events) that are a result of grid disturbances or switching actions.

rated power

Power of wind turbine at a given rated wind speed.

rated wind speed

The wind speed at which the turbine is producing its nameplate-rated power production.


residual-current device


Renewable Energy


Re-scheduling of power plant on short notice to solve congestion in the grid.


"Physical quantity in electrical AC systems which lead to a phase shift between voltage and current .

reaction turbine

A turbine which has a different pressure before and after the impeller. It is fully submerged in water and operates under pressure.

reactive power

A component of apparent power (volt-amps) which does not produce any real power (watts). It is measured in VARs (volt-amps reactive).


Reducing Emission from All Land Uses


renewable energy certificate

receiver tube

In a CSP installation, the receiver tube comprises an absorber tube which is inside an evacuated glass tube. A heat transfer fluid is inside the absorber tube. Solar radiation is absorbed by the absorber tube and transferred to the heat transfer fluid. The outer evacuated glass tube acts to minimise heat losses.


Recourse debt, also known as a recourse loan is a debt that is backed by collateral from the borrower. This type of debt allows the lender to collect from the debtor and the debtor's assets in the case of default as opposed to foreclosing on a particular property or asset. In the event that a project cannot service the financing or achieve completion, the financiers have 'recourse' to either cash from the project sponsor or other non–project security.


Reducing Emissions from Deforestation and Forest Degradation

Page:  1  2  3  (Next)