Speaker Bio:
Martina Dabo, MSc Renewable Energy
Managing Director & Chief Technology Officer, QiDO Energy Development GmbH
Ms. Dabo is the Managing Director & Chief Technology Officer of QiDO Energy Development GmbH, providing technical, financial and project management services, project development and research & development for the renewable energy sector.
Previously Ms. Dabo has been the Director of the Wind Assessment division and the Director of Business Development at CUBE Engineering GmbH. Before joining CUBE, Ms. Dabo was the Program Manager for Renewable Energy Systems at TDX Power, a major utility in Alaska, USA. Prior to joining TDX, she managed the Wind Program for the State of Alaska. While working for the State of Alaska, Ms. Dabo was responsible for the State Wind Program, shaping a renewable energy fund of 200 million US and supporting its implementation.
She has experience in wind and renewable energy project evaluations and consulted large national utilities, project developers, governments and other stakeholders in Germany and abroad supporting the implementation of renewable energy technology.
Prior engagements were as Project Manager for a wind farm developer in Maine, USA and Business Development Manager in the aviation industry in Maine, USA.
Ms. Dabo has a Master of Science with distinction in Renewable Energy Technology from the University of Ulster, UK. Ms. Dabo holds a commercial pilot license and worked for over 10 years as pilot for the German airline Lufthansa.
Presentation Notes:
Slide 2
The presentation will cover following topics –
- The problem of small project wind measurements
- Wind resource assessment standards
- Today‘s solutions for small project wind resource assessment
- The time is right to develop a new standard
- Small wind power curve testing did it too
- Conclusion
- Further ideas for island nations
Slide 4
The wind campaign cost for small projects present a large portion of the overall project cost in a phase where funding is harder to obtain. In a small project about 10-15% of the overall project cost can typically be accounted for the wind measurement campaign, whereas in a large project this portion is less than 1%. This presents a large hurdle for a small project developer to overcome, especially in the sensitive phase of project feasibility evaluations where the investment is high risk and the project’s success and implementation is not yet guaranteed.
Slide 5
The time to develop a small project is usually quicker than a large project, due to lesser permitting hurdles, lower cost, smaller footprint, and less equipment/material/resources to manage. The only competitive advantage small projects have over the larger ones’. This competitive advantage is reduced with the requirement of a 12 months wind campaign.
Slide 6
Reason for this rigor on small wind is the fact that an inaccuracy in wind speed can result in high uncertainties of wind energy yield. As is commonly known the wind speed influence the yield by the cube (x^3). However much more factors are part of the uncertainty assessment of a wind study, i.e. length of historic data, quality of measurement. ADB states (
; page 4) that an inaccuracy of wind speed of +/- 5% can result in an inaccuracy of AEP of +/- 10%. This is in most cases even conservative. What is not regarded in this argumentation is the fact that most small wind projects are part of a hybrid system, where AEP does not automatically translate 1:1 into revenues, due to other non-related system losses or savings, i.e diesel fuel, dump load benefits such as water pumping. In any case even an inaccuracy of +/-15% can be dealt with if adequately incorporated into the financial model. In most projects even with this inaccuracy a viable business case can still be realized as usually the cost of (avoided) energy is rather high in typical small wind locations.
Slide 8
There are no international standards for wind resource assessments. Several guidelines and recommendations from interest groups exist that target specifically wind resource assessment. The most commonly referenced standard, the IEC 61400-1 is not intended for wind resource assessment but rather for wind turbine design. Certain elements from this standard are borrowed and used out of context. The methodologies used by consultants are based on these elements and/or on the wind resource expert guidelines. But each consultant has a certain leeway on how to interpret these standards and how to apply the guidelines and recommendations.
Slide 10
The industry standard approach for a ‘bankable’ assessment of the potential energy yield of a wind farm requires the following main features:
•Wind measurement following the international standards and recommendations regarding the height of mast, quality of recording instruments, and their configuration on the monitoring device
•Long-term extrapolation of measured data; in general, the measuring period should be at least one year, with high availability of data, in order to describe as best as possible the total characteristics of wind.
•Wind field modeling made with recognized software like WindPro, WAsP etc.
•Wind turbine performance modeling
•Uncertainty assessment of the above aspects
A common term for the process flow of wind energy yield assessment is the MCP approach:
Measure → Correlate → Predict
Slide 11
The existing tools are based on similar approaches that compromise time and budget for small wind resource project development with required accuracy and reduction of uncertainties for the confidence of project sponsors.
They are similar to the methodology for large turbines, with the difference to replace actual met mast with ‘virtual’ met mast (commercially available product), or similar forms of verifying the local wind. The rest of the methodology (MCP) remains the same.
With a battery of case studies in different climates, geographical and topographic regions, one can aim to showcase the relative accuracy of the solutions of today and raise the awareness and confidence of funding institutions to accept this approach.
Slide 12
As presented on the previous slide, the approach for a ‘bankable’ wind assessment of the potential energy yield of a small wind farm follows the exact same MCP sequence as the one for large scale. The only difference is the use of virtual met mast (VMM) data instead of wind measurement data.
It will be a matter of time that more data will be available to verify the accuracy of the VVM and more sophisticated modeling will increase the quality of the synthesized data.
Additionally one could perform ‚spot checks‘with LIDAR measurement. If available locally on a rental basis, this could be a cost-effective alternative of a (semi) permanent installation of a met mast. Of course the longer the measurement period, the better the correlation results, but also short term measurements can already give some (limited) insights.
The quality of the VMM depends largely on the geography and topography of the location. In general the more complex a site it in terms of topography and topology the less accurate the VVM data are. In addition ‘remote’ locations that do not have a dense network of meteo stations (used to verify the accuracy of the mesoscale modeling for the VVM) the less accurate the VVM data are as well. Additional local data should be obtained to verify the VVM data. Examples for local data could be from sites that typically collect data for their purposes such as hospitals, industrial sites, environmental measurement stations, etc. In essence the use of VVMs is the only ‘non-standard’ element in the otherwise ‘standardized’ wind resource assessment sequence. Hence the introduction of a new small wind standard is not be a big leap of faith.
Slide 13
One example of a validation process for virtual data from US based AWS Truepower. More information can be found on their website.
Slide 14
Another example of a validation procedure is shown and introduced by the French base company Meteolien. They have developed a wind resource assessment methodology targeting specifically small wind turbines. In cooperation with meteofrance they have developed a comprehensive database for France.
Slide 16
The time is right, and the industry needs to act upon accepted wind resource assessment standards for small projects that do not penalize and block small project development. All elements are there today, from a real and viable need, funding, high quality solutions with acceptable uncertainties, professional project developers and willing project sponsors. All that is need now is one umbrella that merges these elements and pushes for an industry accepted and internationally accepted small project wind resource assessment standard. The result will be rewarding for all stakeholders and will catapult the small project developments into wind revolution 2.0. The development of such standard needs stringent trials and verification by experts around the world, but under the auspice of one potent and influential organization it can be done within a year as the main work has already been done. The time is right.
Slide 18
That such a paradigm shift can be done is shown with the example of power curve testing. As of 2 years ago the international standard for power curve testing, IEC 61400-12, was a cumbersome and stringent procedure. It still is. But at least the testing environment has been adapted for small scale turbines in such a way that no met tower is required anymore for the power curve testing on site. The rest of the test batteries still remain the same for both scale project, which is necessary in order to give a good indication of appropriate turbine operations during their entire lifetime. An overview of the tests can be seen on this slide.
Slide 19
The mentioned new standard for small wind turbines is called 61400-12/2. The wind resource is measured with the nacelle anemometer. The nacelle anemometer type and its influence from the nacelle is calibrated at a test site. The results of the disturbances from the nacelle as well as from the terrain are identified based on data from installed met towers at the test site. A transfer function is created that can be applied as a correction factor to the nacelle anemometers at the project location. This is the basic idea in a nutshell, the overview of the procedure can be seen on this slide. More details are in the standard itself.
Slide 21
The conclusion is -> start now, because:
Alternative solutions today for wind resource assessment without wind met masts result in somewhat higher but acceptable uncertainties, and are a cost effective substitute.
The small industry has a need for quality, affordable and timely wind resource assessment, the funding institutions are willing to sponsor, developers can implement project professionally.
A willing champion has to be identified under whose umbrella a group of experts can validate the existing solutions, develop and implement a new standard that is internationally recognized.
Slide 23
Raising awareness of the challenges of small project development is the first steps, mostly already underway with events such as this one, but can be also conducted on a more regional or local level. Usually those local awareness outreach efforts are driven by a project developer. This adds to the project cost and in the end helps all other developments in the region. To locate those local workshops at a more regional level would benefit all project developments in the area.
Further ideas to foster small project development in island nation is to group needed equipment, expertise, staff, and funding together and manage those on a revolving loan basis at little or no cost to the members. Until the small wind resource assessment standard is officially recognized there is still a need for onsite wind measurement. Either for projects and/or for the verification of the virtual data. Wind measurement towers and LIDAR could be purchased and distributed for a limited time and then moved to the next project site.
A regional renewable energy fund could bridge the gap of necessary upfront or Greenfield funding and project funding.
Finally a circuit rider program that sends ‘fast response teams’ of experts where a project is stalled due to lack of knowledge or expertise can help to get projects toward implementation where otherwise they would be terminated.
All of the above ideas already exist somewhere in the world in one form or the other but deserve to gain wider attention as they can be quite efficient in fostering small project development.
Slide 24
Thank you for your attention. Do not hesitate to contact me anytime for further information:
MARTINA DABO
Managing Director | Chief Technology Officer
QiDo Energy Development GmbH
+49 173 4120095 | +49 30 755 488 00 |
Grünbergerstr. 84 | 10245 Berlin | Germany
www. qidodev.eu
Take-Away-Points:
- The time is right for an international small project wind resource assessment standard
- All elements are in place
- A champion organization is needed under whose umbrella this standard can be developed and implemented
- The standard would reduce unnecessary burdens for small project development and foster growth
- It has been successfully done for small wind turbine power curve testing
- Other ideas to foster small projects exist
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