Point explanation! NEDO “Offshore Wind Observation Guidebook” Part 2



In April 2023, the National R & D Corporation New Energy and Industrial Technology Development Organization (NEDO) has been in Japan for the first time in Japan.Global style observation guidebookWas released.

This guidebook specifically summarizes the information on the wind -ups and windmills that are essential for offshore wind power plants and windmill design. In order for you to make effective use of it, Relatec explains the points from the viewpoint of the wind conditioner consultant.

The "offshore style observation guidebook" is summarized with the latest knowledge in Japan and overseas. The members of Relatech are involved in the NEDO business mentioned above and cooperated with the creation of guidebooks.

First partThen, I introduced the outline of this guidebook and the points you want to focus on. In the second part, it will continue④ and ⑤, andI will talk about what I want to be aware of when using a guidebook.

5 points of guidebooks to note ④⑤

④ Specify the method of pre -accuracy verification

Before observing the wind, it is necessary to verify in advance whether the accuracy of the observation equipment meets the standard.

It is common in Europe to conduct pre -verification, including rider equipment, to reduce observation uncertainty and increase reliability. In particular, pre -verification is an important procedure, as the accuracy of dual scanning rider (DSL) observations may vary depending on the settings of users.

In the accessory B (p.47) of the guidebook, with DSLSingle Canning Rider (SSLThe method of verifying accuracy using the observation data of the windbun mast is described. 

Figure 1 Figure 1. Precision verification examples and thresholds to be referenced (reference 2)

However, this item does not show what kind of site (observation site) actually (observation site) should be verified in advance.

In order to prepare a verification site on your own, not only will you pay for the site, but it also needs to show the validity of the site itself, which can be a hurdle with a high precision verification.

Currently, Relatech has developed a pre -verification site at Mutsu Ogawahara Port, Aomori Prefecture, along with the Kobe University and the Japan Meteorological Association in the NEDO business (reference 2,3).

It is open to the public as a site that anyone can use, so please use it actively.(Scheduled to release HP in the near future)

Figure 2 Mutsu Ogawa Site, Aomori Prefecture, which is open as a test site

⑤ How to complement effective data rates and data default periods

When performing annual observations, the correct evaluation cannot be performed if you do not get a certain level of valid data. Therefore, the threshold of the effective data to be acquired is shown in the guidebook (p.34) after referring to existing guidelines (such as reference 4).

For example, an observation using a doppler rider that measures the speed of the wind by reflecting the laser in the air and reflecting the dust in the air can cause a period in which the observation value is missing. If the air is very clear, the laser will not be reflected and will not be able to measure the wind, and if there is rain, snow, or fog, the laser will be rebuilt and you will not be able to obtain data.

In addition, the floating rider system (FLS) is assumed that the missing period will occur due to maintenance etc.

Due to various factors, if the data is missing or an abnormal value, there is a method of complementing observation data such as the wind -conditions mast (mm).

The guidebook lists the specific method of the Measure-Correlate-Predict (MCP) method (MCP) and the method using double-bias correction (P.35), and shows the reference. In addition, the tolerance criteria (such as regression formula, etc.) for using the complementary method are also described. 

Figure 3 Image of observation value complement by MCP method

One thing to keep in mind is that these standards in the guidebook are "values ​​to be referred to", and there is always "equivalent" as required for wind firms authentication.

Four issues that are not covered in the guidebook

This guidebook has been shown from the acquisition of the license required for FLS to the method of installing SL, making it an easy -to -understand book for those who are starting to investigate offshore. However, there are some items that are not covered.

With the expectations of future updates, I picked up the issues that are not covered at present.

① Oki -ya -style survey method

In the guidebook, DSL is recommended as an observation method of the only rider's turbulence strength, but in fact, DSL cannot be used in the Okinai -style survey, which is expected to have floating offshore wind.

The SL laser irradiation range is longIt is 10 km, and from the viewpoint of the data acquisition rate, it is considered that the range that can be observed stably is about 4 to 5 km. In other words,As long as the coastline can be observed by DSL, you can cover only the shallow sea area (implanted offshore wind).

Commentary ③As described in, the measurement of turbulence strength using FLS is not described in this guidebook because there is no sufficient technical results at present. However, the research results of FLS's turbulent strength measurement (for example, references 5 to 9) have been reported.

In the future, we hope that the information on the offshore windshability survey method will be added by promoting research related to turbulent intensity measurement by FLS observation.

Figure 4 Observation image of offshore

② Further verification in DSL observation

In the guidebook, DSL observation was recommended as an observation method of offshore winds, including turbulence strength. However, DSL observation is not a perfect tool that can measure turbulent strength, but it understands that there is a part that has not yet been solved in the same way as a wind -up mast (cup wind speed meter, vane -style meter). need to do it.

For example, as the guidebook states that the length of the range gate may underestimate the standard deviation of the wind speed, how the measurement accuracy changes depending on the device side. need to do it.

Also, the accuracy of the wind speed standard deviation (5%or less; guidebook P.47) and the elevation angle of the gaze (less than 5 degrees; the same P.18), the threshold and reference value described as the recommendation. It is required to update based on the accuracy verification that is the basis.

In Europe, technical development is being developed by the Joint Industry Project (JIP) method, and ridors have been implementing rider's turbulence strength measurement (for example, references 10). In this case, based on the windmill load, the accuracy standard of turbulence intensity by rider equipment is discussed.

In Japan, the turbulent strength measurement by DSL observation has already been adopted, and we believe that it is necessary to work on the above -mentioned issues with a speedy research and development using the JIP system as an example. 

Fig. 5 Analysis results regarding turbulent strength measurement using rider equipment, etc. (Reference 10)
The vertical axis shows a relative error by each measurement method for the standard (cup wind speed meter).

③ Observation method for evaluation of power generation

In a wind -powered power plant construction, "Wind Conditional Evaluation (Windmill Design Evaluation)" and "Electric Current Evaluation" are performed.

The "Wind Conditional Evaluation" derives the wind parameters required for windmill design, and a method of satisfying the certification acquisition guidelines is required. The guidebook mainly introduces the contents aimed at acquiring this authentication.

On the other hand, there is no description of points that are important in the wind status observation or the concept of uncertainty evaluation in order to implement "power generation evaluation".

We hope that the number of wind -based observations using this guidebook will increase and update the opinions of all the wind -related people in the future.

④ Verification and review of the standard

Commentary ②As described in the guidebook, the criteria specified in the guidebook may need to be verified from both the actual situation of the observation site and the accuracy collateral.

actual,"The installation standards such as DSL are too strict and not suitable for the actual situation. "I hear the voice of the site, so I think there is room to update through future research and development.

For example, there is still room for discussions on the "representative radius (set to include all planned windmills within the representative range of the observation point)" described in the guidebook (P.11). The guidebook states that "the same 10 km as the standard for land flat terrain is the representative radius of the sea", but based on this, it is very very large when planning a waters that spread long in the direction of the coastline or a vast offshore farm. You need a lot of observation points, and in reality you need a fairly strict wind observation.

Overseas, there is no guideline or standard on the radius of the representatives of the sea, so it is necessary to consider further examinations.

Fig. 6 Image of representative radius in windmill placement and observation points (flat terrain, offshore)

Ueda and others (2022) (Reference 10) include the introduction of the guidebook from the creator's point of view, so I hope you can refer to it.

What was announced this time is a technical guidebook that summarizes the recommended methods for offshore wind observation. Windfarm authentication does not always pass if you follow the description, as in the guidelines. It is also important to note that in terms of power generation evaluation, it is not possible to handle it.

However, the clear standards for all observation items have been indicated so that highly accurate observations can be performed.I feel that it is a big move for the domestic wind industry.

In the future, various knowledge will gather and update information will lead to more practical guidebook creation. With the issuance of this guidebook, we hope that offshore wind power generation will become increasingly exciting.

  1. NEDO, offshore style observation guidebook, 2023,
    Kobe University Mutsu Ogawara Yorai Winding Observation Examination Site,
  2. Mizuki Kohana, Teruo Osawa, Susumu Shimada, Shogo Uchiyama, Kazuhiro Kawamoto, the necessity of pre-verification in rider observation and the study of the Ogawara site on the Mutsu Ogawara site, the 44th Wind Power Energy Usage Symposium Preliminary Collection, pp.124-127 , 2022.
  3. Carbon Trust, Owa Roadmap for the Commercial Acceptance of Floating Lidar Technology, 2018.
  4. Masago Uchiyama, Teruo Osawa, Yuji Aso, Mizuki Kohana, Gohizo Araki, Kohei Araki, Kohei Takada, Mutsu Ogawahara's accuracy characteristics, 44th Wind Energy Use Symposium Preliminary Collection, pp.120- 123, 2022.
  5. Teruyuki Asakura, Teruo Osawa, Yuji Aso, Land upright for the floating rider performance evaluation (Part 2), 44th Wind Energy Use Symposium Preliminary Draft, pp.116-119, 2022.
  6. Fujimoto Fujimoto, Teruo Osawa, Mizuki Kohana, Gohei Misaki, Kohei Takata, vertical rider's observation characteristics, 44th Wind Energy Usage Symposium Preliminary Draft, pp.132-135, 2022.
  7. Moreno M., Bellanco M. J. J. J. J. J. J. J. J. J. J. J. J. J. Ty WHEN COMPARED TO an offshore met Mast. Wind Europe Offshore 2019, 2019,.
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  9. St. Pé, Alexandra, Weyer, Elie, Campbell, Iain, Alntsen, Alexandra E., Alexandra E., Kondabala, Nikhil, Mibus, Marcel, Marcel, Coulombe-Pontbriand, Black, Andr EW H., Parker, Zach, Swytink-Binnema, Nigel, Jolin, Nicolas, Goudeau, Barrett T., Meklenborg Miltersen Slot, René, Surenningsen, Lasse, Lasse, Lasse, Joseph C. Y., Josephu, Mithu AR, Dale, Fric, Thomas,… Matthew Meyers. (2021). cfars Site Suitability Initiative: An Open Source Approach to Evaluate The Performote Sensing Device (RSD) TurbUlence Intense Intense Measurement S & Accelerate Industry Adoption of RSDS for Turbine Suitability Assessment. Zenodo.
  10. Introduction of Yuko Ueda, Tomoya Iwashita, Hioki Hioki, Hiroshi Imamura, NEDO Water Winding Statement Observation Guide Book, 44th Wind Energy Usage Symposium Preliminary Collection, pp.136-139, 2022.

As a wind -up consultant, Relatech will conduct an optimal air -based survey using "observation" and "estimation" for wind power. Please feel free to contact us if you have any consultation on the style.