How to Check a Chinese Wind Farm's Grid Connection and Curtailment: The Connection File, Grid-Code Capabilities, How Curtailed Energy Is Measured and Reported, What Counts Against the Utilisation Rate, and Where Assessment Fees Arise

Short answer. A Chinese wind farm's connection rests on a signed dispatch agreement and power purchase contract — without them it may not operate — and on a list of capabilities the dispatch body may test and assess; its curtailment is measured by rules that exclude the farm's own outages, that count only system-caused losses toward the utilisation rate, and that are reported and disclosed on a fixed monthly calendar. China's reported national wind utilisation rate was 94% in 2025 and 95.9% in 2024. This guide reads the connection file, the capability list, the measurement rules, the exclusions and the assessment mechanics in that order. It quotes no provincial rate, project curtailment figure or assessment amount.

1. The national picture

The NEA's February 2026 release on 2025 renewable grid operation reports 120 GW of wind added in 2025 (+51%), of which 110 GW onshore and 6.59 GW offshore, with the "Three North" regions taking 79% of additions; cumulative wind capacity of 640 GW (+23%; 590 GW onshore, 47 GW offshore) at end-2025; wind generation of 1.13 trillion kWh (+13%); and a national average wind utilisation rate of 94%, against 95% for solar. The 2024 release had reported 95.9% for wind, on 991.6 billion kWh of generation (+16%). A national average says nothing about a given farm; the rest of this guide is about how the farm's own number is produced.

2. The connection file

The NEA's Provisions on Grid-Connected Operation (国能发监管规〔2021〕60号, 21 December 2021, valid five years, replacing the 2006 power-plant provisions) apply to wind and other generators directly dispatched by provincial or higher dispatch bodies; they require a dispatch agreement and power purchase contract, signed with reference to the national model texts, before connection; they require entities to follow the operating mode and dispatch curve set by the dispatch body or cleared by the market; and they have the dispatch body assess unplanned outages or disconnections, deviations in executing dispatch instructions and new-energy power-forecast deviations under local implementing rules. The model texts are those issued by the NEA and SAMR on 28 December 2021 (国能发监管规〔2021〕67号), which include a model dispatch agreement for new-energy stations, require connection and purchase agreements in China to follow them (the earlier six texts, including the 2014 wind-farm texts, no longer apply) and require both parties to file signed texts with the local NEA dispatched office. Under the 2021 provisions, agreements and contracts must be filed within 10 working days of signing.

NDRC Order No. 15 (in force 1 April 2024) defines the guaranteed-purchase scope as the export of projects that are in the renewable plan, approved or filed, and compliant with connection standards; it requires the grid company to build or upgrade the project's supporting grid facilities under the relevant plans, to coordinate construction timing with the generator and strive for simultaneous commissioning, to use temporary connection or similar means to the greatest extent where the works cannot be commissioned on time for objective reasons, to provide connection design information and process timelines, and to state the connection-works schedule in the connection agreement. The technical standard behind "compliant with connection standards" for onshore wind is GB/T 19963.1-2021, a current recommended national standard issued 20 August 2021 and implemented 1 March 2022. The connection file to ask for is therefore: the approval or filing, the dispatch agreement and purchase contract on the 2021 model texts with their filing receipts, the connection agreement with its works schedule, and the grid-related test reports.

3. What the farm must be able to do

The 2021 provisions' technical-management list for new-energy stations requires an adequate short-circuit ratio; turbine over-voltage, low-voltage and frequency protections meeting standards; primary frequency regulation, fast voltage regulation and low/high-voltage ride-through with voltage and frequency tolerance in principle equal to synchronous units; reactive-power regulation and automatic voltage control, with an AVC sub-station and, where needed, synchronous condensers or STATCOM/SVC; an active-power control system that executes dispatch signals; power forecasting with reporting of forecasts, single-turbine files, meteorological data, installed, available and theoretical power at the required accuracy; and prompt reporting of large-scale disconnection with no reconnection without permission. The national test procedures for two of those capabilities are GB/T 36994-2018 (grid-adaptability test) and GB/T 36995-2018 (voltage fault ride-through test), both current recommended national standards issued 28 December 2018 and implemented 1 July 2019. This guide cites the standards from their information pages only.

The NEA's Q&A on the provisions says they have 6 chapters and 32 articles, were renamed from the 2006 power-plant provisions to cover new energy, new storage and load-side entities, add the duty to execute market-cleared operating modes and curves, strengthen assessment of unplanned outages and disconnections, and require dispatch and trading bodies to disclose assessment and refund results to all participants. For a retrofitted farm, the 2023 retrofit and decommissioning measures make the grid company responsible for expanding the export works, for connecting listed projects with simplified procedures, and for guiding grid-related tests and re-signing the dispatch agreement and purchase contract; when turbines reach design life the generator must carry out a safety assessment reported to the energy authority, the NEA office and the grid company.

4. How curtailed energy is measured and reported

The NEA's 2022 Measures for Monitoring and Statistics of Wind Farm Utilisation Rate define curtailed (受限) energy as energy the farm could have generated but did not, after excluding its own equipment faults, defects and maintenance; use the nacelle-anemometer method as the main calculation method, with sample-turbine and met-mast extrapolation methods allowed by agreement with the dispatch body; set the curtailment period by the dispatch body's curtailment and release instructions or automatic control records, with both sides recording time, output limit and reason; and require the farm and dispatch body to test the method's accuracy during unconstrained periods of at least 6 hours. Each farm reports its monthly generation information by the 5th of the following month to the dispatch body and on the national platforms; the provincial grid company compiles, checks and reports by the 15th and discloses results to the farms; a farm disputes through the dispatch body and, failing that, the NEA dispatched office; the NEA's national monitoring centre monitors monthly, evaluates quarterly and publishes provincial results; and the measures replaced the 2012 curtailed-energy calculation method with a provisional five-year validity.

CNWattHub editorial method: reconcile three records for the same month — the farm's own nacelle-method estimate, the dispatch body's instruction log of limits and reasons, and the grid company's disclosed figure — and treat any gap as a question for the dispatch body before it becomes a question for a buyer.

5. What counts against the utilisation rate, and what does not

The NEA's May 2024 notice lets some regions with good resource conditions relax their new-energy utilisation-rate target, in principle to no lower than 90%, with annual dynamic evaluation; makes provincial energy authorities responsible for the target, reported to the NEA which may adjust it; says the rate is calculated counting only system-caused curtailment, with grid companies publishing the criteria for "special-cause" curtailment; and requires monthly disclosure to each wind farm of its utilisation rate, available generation, actual generation, curtailed energy and special-cause curtailed energy. Document 136 (2025) adds that energy not exported because of a project's own bidding after market entry is not counted in utilisation-rate statistics and assessment, and that storage may not be made a precondition for approval, connection or export of new projects.

Order No. 15 draws the same line for the purchase obligation: a project's export is split into guaranteed-purchase volume and market-traded volume (the latter bought by retailers and users), and energy lost because of the generator's own reasons, grid security constraints, grid maintenance, market bidding or force majeure is outside the guaranteed scope, which the grid, dispatch and trading bodies must record with reasons. The order requires the dispatch body to give renewable generation priority in daily planning and real-time dispatch under national and market rules, requires the dispatch body and trading centre to disclose the previous month's purchase information to each generator by the 8th, and makes grid, dispatch or trading bodies that fail to purchase as required liable for the generator's loss with a possible fine of up to one times the loss if they refuse to correct. The practical reading: a farm's "curtailment" as experienced is the sum of system-caused limits (counted), special-cause limits (disclosed separately), its own outages (excluded) and, once in the market, bid-driven non-dispatch (excluded) — and each of the four carries a different consequence.

6. Where the money leaks: assessment and refund

Under the 2021 provisions, regional NEA offices write regional implementing rules and provincial offices may set different assessment and refund standards; the dispatch body assesses on a dedicated-account, balanced-budget basis; spot-market pilot regions may not assess twice what a market mechanism already achieves; assessment is in principle by charging fees that are returned as rewards or by ancillary-service contribution; the trading centre publishes assessment and refund results by the 10th of the following month, with 3 working days to object and 3 working days for the dispatch body to answer and appeal to the NEA dispatched office; and agreements and contracts must be filed within 10 working days of signing. The NEA's 2021 Q&A put ancillary-service costs at about 1.5% of total electricity charges at the time against a typical 3% or more internationally. The regional implementing rules were not retrieved; the farm's assessment exposure (forecast deviation, unplanned outage, dispatch deviation) is set there.

Checklist

Scope limits

National rules and NEA aggregates only. Regional implementing rules (the "two detailed rules") with their assessment tariffs were not retrieved; GB/T 19963.1-2021, GB/T 36994-2018 and GB/T 36995-2018 are cited from information pages; offshore connection (GB/T 19963.2) and offshore retrofit measures were not retrieved. No provincial rate, project figure or assessment amount is quoted. Not legal, technical or investment advice.