FAQ

FREQUENTLY ASKED QUESTIONS

Reliable yield figures are crucial for any wind energy project, which is why a legally sound wind assessment is indispensable for economic success. Whether the issue is securing financing or classification under the German Renewable Energy Sources Act (EEG), you need physical precision that remains valid for the entire 20-year lifespan, not optimistic estimates.

This FAQ section summarises our in-depth expert knowledge of professional yield forecasting in accordance with TR6, as well as the relevant technical guidelines (TR5 and TR10) for determining wind potential, reference yield and site quality.

A verified wind assessment is a mandatory prerequisite for the ‘bankability’ (i.e. financing) of a wind energy project, as it quantifies economic risk. Without this verification, banks and investors will not provide capital. At 4cast, we provide this reliability by combining meteorological expertise with calculations that comply with standards and can withstand any due diligence review.

4cast – heartbeat of renewables

The quality and acceptance of wind energy assessments depend crucially on adherence to technical standards. In this regard, the Technical Guidelines (TR6) of the FGW e.V. for determining wind potential and energy yields are paramount. Furthermore, DAkkS accreditation according to DIN EN ISO/IEC 17025 represents the gold standard for recognition by banks. To ensure maximum legal certainty, 4cast prepares all analyses in strict accordance with these specifications. Only through the consistent application of these standards can reliable financing for wind energy projects be guaranteed.

4cast – heartbeat of renewables

In the German Renewable Energy Sources Act (EEG), the reference yield serves as a standardised benchmark to determine the efficiency of a wind turbine at a specific site. It defines the amount of energy that a turbine would generate at a legally defined reference location. We calculate this value precisely for your turbine type, as it forms the basis for the correction factor and therefore the amount of your feed-in tariff.

4cast – heartbeat of renewables

In order to create a legally compliant wind energy assessment in accordance with the standards of FGW e.V., 4cast requires precise data. Only a technically sound yield forecast in accordance with TR6 will ensure that the project is fully accepted by banks and investors.

– Site coordinates and layout: The precise positions of the planned wind turbines, as well as information on the topography and terrain roughness.

– Tailor type and specifications: Definition of the planned turbine types, including hub heights and manufacturer-specific power curves.

– Wind measurement and reference data: Existing on-site wind measurements or reliable long-term time series from regional reference sources to provide a robust data basis.

– Environmental factors: Data on existing or planned neighbouring wind farms (to avoid park effects), as well as on obstacles such as forested areas or buildings.

– Operational restrictions: Permit-relevant requirements regarding noise protection or shadow flicker that directly influence yield calculations.

4cast – heartbeat of renewables

Meteorological expertise allows wind data to be interpreted physically (e.g. stratification and thermal effects), whereas purely statistical methods often only extrapolate past values. This physical approach results in more accurate long-term corrections and reduced uncertainty. This is our “Unfair Advantage” at 4cast. We understand the atmosphere, not just the spreadsheet, which reduces the risk to your project.

4cast – heartbeat of renewables

The standard processing time for a full yield assessment is up to eight weeks from receipt of all the necessary data (measurement data, layout and operational data). If you require a transaction (closing) or financing round to be completed within a shorter timeframe, please contact us – we offer prioritised processing services.

4cast – heartbeat of renewables

For repowering projects, historical data from existing turbines is the most valuable indicator of future performance. Accurate analysis of operational SCADA data often provides more precise forecasts than simulations. We use this historical data, correct for downtime and throttling, and correlate it with the new hub height. This significantly reduces uncertainty in wind energy assessments and improves financing conditions.

4cast – heartbeat of renewables

Yes, ground-based remote sensing systems (LIDAR, SODAR and measuring masts) are recognised as legitimate measurement sources in accordance with Technical Guideline TR6, provided they meet the required quality standards. This data often offers more flexible application possibilities than measurement masts. We routinely integrate and validate this measurement data in our yield assessments to ensure the data basis for your project is robust.

4cast – heartbeat of renewables

The amount of credit you receive for your wind farm is determined by uncertainty discounts. Banks usually base financing on the P75 value – the more uncertain the appraisal, the less can be financed.

P50 is the statistical expected value (50% probability).

– P75/P90 are the safety thresholds for banks (75% and 90% probability, respectively).

– Our advantage: 4cast reduces these discounts by providing precise yield forecasts based on TR6. We minimise the gap between the expected and safety values to maximise the project value for your financing.

4cast – heartbeat of renewables

Alternatively, you can send your enquiry directly to sales@4-cast.de.

OR

Alternatively, you can use the contact form at the bottom of the website. Once we receive your enquiry, we will assess its feasibility and contact you to discuss the next steps.

4cast – heartbeat of renewables

Technical Guideline 10 (FGW TR10) sets out the mandatory procedure for assessing site quality following the commissioning of wind turbines. According to the German Renewable Energy Sources Act (EEG), a comparison must be made between the actual energy yield (based on SCADA data) and the theoretical reference yield after five, ten, and fifteen years of operation.

Having a valid data foundation from the planning phase is crucial for a legally sound TR10 assessment. Although 4cast does not conduct the TR10 assessment itself, our precise TR6 yield reports provide the necessary reference basis. An accurate TR6 forecast is essential for securing compensation claims against the grid operator and minimising the risk of clawbacks during the site quality assessment.

4cast – heartbeat of renewables

Complete operational data is essential for calculating site quality in accordance with TR10. Specifically, the following are required:

– Master data: Plant type, Hub height, Exact coordinates

– Operational data: SCADA data (10-minute averages) for the assessment period.

– Status data: Logs of availability, maintenance and external curtailments (e.g. feed-in management).

4cast – heartbeat of renewables

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