A comprehensive online glossary of terms and definitions related to built environment, heating, ventilating, and air conditioning (HVAC), as well as refrigeration, building envelope, electrical, lighting, water and energy use, solar power, concentrating solar power (CSP), and measurement terms.
There are currently 6 terms in this directory beginning with the letter Q.
a procedure employed for verifying the accuracy of the measuring techniques (temperature, airflow rates, duct heat calibration) employed in determination of the room heating effect. This qualification procedure is periodically employed in determining the room heating effect.
a monitored condition used to establish active or inactive status for a measured parameter.
a process for evaluating a subset (sample) of the total population. The sample is based upon a known or estimated probability distribution of expected values; an assumed statistical distribution based upon data from a similar product, assembly, or system; or a random sampling that has scientific statistical basis.
quantum efficiency (QE)
The ratio of the number of charge carriers collected by a photovoltaic cell to the number of photons of a given energy shining on the cell. Quantum efficiency relates to the response of a solar cell to the different wavelengths in the spectrum of light shining on the cell. QE is given as a function of either wavelength or energy. Optimally, a solar cell should generate considerable electrical current for wavelengths that are most abundant in sunlight.