Ammonit Measurement GmbH

Wrangelstrasse 100, D-10997 Berlin (Germany)T: +49 30 6003188-0, E: info@ammonit.com www.ammonit.com measuring wind and solar power www.ammonit.com

Ammonit Wind Resource Assessment Systems

Standard Wind Measurement System System components

Simple Terrain • Meteo-40 data logger• Steel cabinet with terminal for Meteo-40• GSM/GPRS modem with omni-directional antenna• Power supply system with solar module and solar charge controller• 4x Anemometers, calibrated (Thies First Class Advanced)• 3x Wind vanes, digital (Thies First Class TMR)• 1x Combined air temperature (Pt1000) and humidity sensor with

weather and radiation shield• 1x Barometric pressure sensor

Optional to met mast installation*• ZephIR 300** (LiDAR) or AQ510 wind fi nder*** (SoDAR) including

power supply system

* see fi rst page “Standards for wind measurement” - TR6 (Rev. 9)** verifi ed for wind energy assessments in benign conditions by DNV-GL*** classifi ed according to IEC 61400-12-1 (Edition 2) by DNV-GL

Complex Terrain • Meteo-40 data logger• Steel cabinet with terminal for Meteo-40• GSM/GPRS modem with omni-directional antenna• Power supply system with solar module and solar charge controller• 4x Anemometer (Thies First Class Advanced)• 3x Wind vane, digital (Thies First Class TMR)• 1x 3D Ultrasonic anemometer or propeller anemometer• 1x Combined air temperature (Pt100) and humidity sensor with

weather and radiation shield• 1x Temperature (Pt100) sensor with weather and radiation shield• 1x Barometric pressure sensor

Additional to met mast installation• ZephIR 300 (LiDAR) or AQ510 wind fi nder (SoDAR) including power

supply system

Ammonit supports you in designing your individual measurement system for wind resource assessment. We look forward to hearing from you: info@ammonit.com or +49 30 6003188-0.

© Copyright Ammonit 2016Thanks to AQ System, Ge:Net and ZephIR Lidar for providing the photos of page 1 and 2 of this brochure.

Ammonit Wind Resource Assessment Systems

Ammonit Wind Resource Assessment Systems

Prior to setting up a wind farm, the local wind conditions have to be measured for site assessment. To do so, accurate and reliable wind measurement technology is required. The installed equipment has to perform as precisely as pos-sible as the data quality is essential for designing a reliable and economical wind farm. A small discrepancy in the evaluation of wind speed data drastically multiplies the discrepancy of the calculated wind power.

Wind resource assessment systems offered by Ammonit meet the highest standards of quality and are designed for the local site conditions with regard to measurement accuracy, communication and power supply system.

Advanced measurement systems for accurate and reliable wind measurements.

Standards for wind measurement

IEC 61400-12-1The most important standard is IEC 61400-12-1, which specifi es the correct set up of a met mast including booms as well as its positioning, alignment and type. It describes the quality of sensors installed on the mast with regard to accuracy and reliability. It defi nes a set of criteria with regard to data quantity and quality.The IEC standard is currently being updated. The new standard will include rules for using ultrasonic sensors and remote sensing devices for site assessment. We expect the updated IEC to be published at the end of 2016.

MEASNETThe “Evaluation of site-specifi c wind conditions” procedure has been agreed by MEASNET, which is a network of measurement institutes. The procedure describes the process of site assessment including data collection, evalua-tion and interpretation. It refers to IEC 61400-12-1 with focus on data quality, plausibility and integrity.

TR6 (Rev.9)The guideline TR6, published by the German “Fördergesellschaft Windenergie und andere Erneuerbare Energien”, describes processes for energy yield assessments at sites for wind turbines. It focuses on wind measurement con-sidering met masts as well as remote sensing devices. Under certain conditions, the guideline accepts wind speed and direction measurements only with remote sensing devices - met mast is not required. This guideline is mainly applied in Germany.

Innovative measurement equipment for the wind and solar industry

Ammonit Wind Resource Assessment Systems

Impact of sensors on the AEP (Annual Energy Production)

In order to obtain reliable and accurate measurement data, the installation of high quality sensors is crucial. Refer to the table below to learn more about the impact of measurement errors on the annual energy production. Ammonit products are known for their outstanding performance and quality in various climate zones. Working with Ammonit -approved measurement equipment ensures reliable measurement campaigns with high quality measurement data.

Generated energy error by 1% measurement error

Anemometer Δ1% wind speed measurement error → Δ3% energy

(Up to Δ6% energy, if anemometers are used to calculate the wind profi le.)

Wind vane No direct linear relation, but will lead to poor wind farm design

Barometric pressure sensor Δ1% pressure measurement error → Δ1% energy

Temperature sensor 1° measurement error → 0.35% energy

Humidity sensor with 40°C, 1% measurement error → 0.05% energy

Accurate sensors for reliable measurement campaigns.

Calculation of wind energy

The calculation of the power of the wind energy (P) is based on the Kinetic Energy of moving air molecules. According to Betz’ law wind power is:

P = 1/2 ρ • A • v³where• A is the area• ρ is the air density, ρ = p / (R • T), being p the air pressure, T the air temperature and R the gas constant• v is the wind speed

Therefore, wind speed (v) is the most important parameter, as wind energy (P) is proportional to the cube of wind speed.

Δ1% wind speed ≈ Δ3% wind energy

Ammonit Wind Resource Assessment Systems

Typical Wind Measurement System according to IEC 61400-12-1*

To minimise the uncertainty inherent in extrapolation, it is important to measure the wind speed as near as possible to the hub height of the planned wind turbine. For accurate mea-surement results, the IEC standard specifi es the installation of cup anemometers, which have to be calibrated traceably before and after a measurement campaign. The difference between both calibrations should not exceed ± 0.1 m/s.

A measurement system has to meet the requirements in regard to climate and landscape at the site for the planned wind farm. Hence, you might think of vertical wind measurement and sensor heating. In some cases additional measurement stations might be useful. According to IEC, wind speed, wind direction and air density have to be measured for site assessment. Learn more about the parameters in the following table.

Precise measurements according to international standards.

Parameter Description Installation Sensor

Wind Speed • Most important parameter • Wind energy is proportional to the

cube of wind speed • Measured with calibrated cup ane-

mometers or calibrated ultrasonic anemometers

• Optionally measured with LiDAR and SoDAR devices

• Note: Vertical wind speed measure-ment for turbulence and wind turbine load analysis with 3D ultrasonic ane-mometer or propeller anemometer

• Wind speed measurement at 3 to 4 heights

• Installation of top ane-mometer at a minimum of 2/3 of planned hub height

• 1 backup anemometer below top anemometer

• Additional anemometers at different heights for wind profi le calculations

Wind Direction • Important parameter for wind farm micrositing

• Measured with a wind vane; ultra-sonic anemometers also determine the wind direction

• Optionally measured with LiDAR and SoDAR devices

• Mounting of top wind vane 1.5m below the top anemometer

• Recommendation of addi-tional wind vane at other heights for backup and wind profi le calculations

Air density(Air pressure, air temperature and relative humidity)

• Derived from air temperature and air pressure measurement

• Wind energy is linear proportional to air pressure

• Wind energy is linear proportional to the inverse of air temperature in K

• Air pressure measured with baromet-ric pressure sensor

• Air temperature measured with tem-perature sensor

• Measurement of relative humidity recommended at high temperatures acc. to IEC

• Installation of barometric pressure sensor close to hub height or inside the cabinet with data logger

• Installation of tempera-ture and humidity sensor within 10m of planned hub height

* The IEC 61400-12-1 is currently being updated. See also fi rst page of this brochure.