Temperature sensors (thermometers) for wind energy resource assessments are devices used to measure ambient temperature (in the shade by using a radiation shield), transforming that into an electrical signal to be recorded by a data logger. The ambient temperature, relying on thermometer calibration, is an important variable, since it impacts the density of the air. Hence, it impacts directly the kinetic energy of the wind, hitting the wind turbine rotor. Therefore, it is of direct impact to the energy produced by a wind turbine or wind park (wind farm), and so is the temperature sensor calibration of likewise importance.
For a bankable wind energy resource assessment, it is of importance to measure this variable within a qualified, accredited wind resource measurement campaign, in compliance to MEASNET, IEC and FGW standards, which means taking into account temperature sensor calibration. The measurement should be taken as close as possible to the projected hub heights of the wind turbines in a wind park as to reduce uncertainties, relying on a thermometer calibration being performed at the beginning of the measurement campaign. But also temperature measurements close to the ground level should are taken by a temperature sensor (housed in a radiation shield), that previously has been undergoing thermometer calibration, to provide insight into the atmospheric conditions, i. e. to maintain the stability, instability or neutrality of the atmosphere.
It is important that temperature sensor calibration is performed in compliance to MEASNET, FGW and IEC recommendations.
During the temperature sensor calibration process, the measurand (i.e. the sample to be calibrated) is measured against a normalized reference temperature sensor, in order to give accurate information about the precision of the temperature sensor to be calibrated. To effectively function, the thermometer calibration should be done at regular intervals of about 1 to 2 years, depending on the temperature sensor application and the sensor quality.
The temperature sensor calibration is done as a whole. All the components of the temperature sensor are calibrated together in one line, i.e. transducer, electronics, and cables.
Thermometer calibration to maintain integrity of the results from the temperature sensor.
ProfEC Ventus is a DAkkS-accredited (ilac-MRA compliant) calibration laboratory and offers temperature sensor calibration / thermometer calibration in ranges from about -18 °C … 180 °C as certified ISO calibration.
Combined temperature - relative humidity sensors (combined temp - rh sensor)
Often temperature and relative humidity sensors are available as a combined temperature - rel. humidity sensors (combined temp - rh sensor) that measure both, ambient temperature and relative humidity of the ambient.
Such sensors often are called:
• temperature – relative humidity sensor
• temperature – rel. humidity sensor
• temp - rh sensor
• temp - hum sensor
• temperature – humidity sensor
• rh - t sensor / t - rh sensor etc.
The combination of both sensor elements combined in one single device works pretty fine and there is no obvious disadvantage of using a such like combined temp - rh sensor.
Important for both sensor elements is, may it be individual sensors or combined temp - rh sensors, that for wind and solar energy applications, the sensors are hosted within a radiation shield / i.e. weather guard or weather shield, in order to:
- Avoid direct sun light, since temperature usually is measured in shadow (i.e. within the radiation shield)
- Avoid the sensors elements are getting wet, which may harm the sensor and reduce the functionality
ProfEC Ventus has developed a solution and offers a radiation shield / i.e. weather guard that can host temperature – rel. humidity sensors of several types. In addition, the innovative design also enables to mount a barometer for barometric pressure measurements to the radiation shield, enabling taking measurements close to hub height. For a bankable wind energy resource assessment, it is of importance to measure temperature, relative humidity and atmospheric pressure within a qualified, accredited wind resource measurement campaign, in compliance to MEASNET, IEC and FGW standards. The measurements should be taken as close as possible to the projected hub height of the wind turbines as to reduce uncertainties and to gain valuable insights of the atmospheric conditions.
Relative humidity sensor calibration
Relative humidity sensors (rel. humidity / rh) meant for wind energy resource assessments are devices operated in a radiation shield (weather shield), transforming the measurement signal into an electrical signal to be recorded by a data logger. Relative humidity sensor calibration is important, since the relative humidity directly impacts the density of the air. Hence, it impacts directly the kinetic energy of the wind, hitting the wind turbine blades. Hence, it also is of direct impact to the energy produced by a wind turbine / wind farm (wind park).
For a bankable wind energy resource assessment, it is of importance to measure the relative humidity as part of a qualified, accredited wind resource measurement campaign, in compliance to MEASNET, IEC and FGW standards, thus taking into account relative humidity sensor calibration. The measurement should be taken as close as possible to the projected hub heights of the wind farm turbines as to reduce uncertainties, whereat the sensor should be hosted within a weather guard, i.e. weather shield (radiation shield).
It is important that the relative humidity sensor calibration is executed in compliance to MEASNET, FGW and IEC recommendations.
The relative humidity sensor calibration is the process of measuring the device (measurand) against a normalized reference relative humidity sensor, in order to give accurate information about the precision of the calibrated
rh sensor sample. To effectively function, the rel. humidity sensor calibration should be done at regular intervals of about 1 to 2 years, depending on the relative humidity sensor application and the sensor quality.
The relative humidity sensor calibration is done as a whole. All the components of the sensor are calibrated together in one line, i.e. transducer, electronics, and cables.
Relative humidity sensor calibration is done to maintain integrity of the results from the rel. humidity sensor.
ProfEC Ventus is a DAkkS-accredited (ilac-MRA compliant) calibration laboratory and offers rel. humidity sensor calibration in ranges of 10 % rel. hum. … 98 %rh as a certified ISO calibration.
