Read a wind proposal by separating its rated power, expected annual electricity and contribution at the times the grid needs it. Then examine the site, connection, operating impacts and full project costs. A large megawatt figure becomes useful only when those assumptions are visible.
Ask for the project location, turbine configuration, current development stage and dated generation assessment. An operating project should also provide actual output and availability records for the period being discussed.
Connect megawatts to megawatt-hours
DOE’s turbine explanation describes how aerodynamic forces turn the rotor and drive a generator. Rated capacity in megawatts (MW) is a power rating. Electricity generated over time is energy, commonly reported in megawatt-hours (MWh).
On a narrow screen, scroll the table sideways. Keyboard users can focus the table region and use the arrow keys.
| Quantity | Meaning | Evidence question |
|---|---|---|
| Nameplate capacity, MW | Sum of rated turbine power | Which turbines and how many are included? |
| Annual generation, MWh | Energy produced over the stated year | Is this modeled or metered, gross or net? |
| Capacity factor, % | Energy divided by rated power × period hours | Which losses and calendar period are included? |
| Availability, % | Time equipment is ready under a defined rule | How are maintenance, wind conditions and grid stops counted? |
| Grid contribution | Output available when the system needs capacity | Which system study and time pattern support the claim? |
Fictional wind plant: 20 MW × 8,760 hours × 0.35 capacity factor = 61,320 MWh per ordinary 365-day year. A 0.25 case produces 43,800 MWh; a 0.45 case produces 78,840 MWh. These are illustrative assumptions, not forecasts for a real site.
A 35% annual capacity factor summarizes energy across the year. It can arise from many different hourly output patterns. Use time-series data to understand calm periods, peaks and seasonal variation.
Ask how the output estimate was produced
Request the measurement duration, measurement height, long-term weather adjustment and uncertainty range. The estimate should identify the turbine power curve, air-density assumptions and losses from wakes, electrical equipment, maintenance, icing where relevant and curtailment. Check whether the advertised output already subtracts those losses before applying any further reduction.
DOE’s wind questions and answers discusses resource, costs and site-dependent effects. A regional wind map is useful for initial screening; a proposal needs evidence for the actual terrain and turbine height. Nearby trees, buildings and terrain are especially consequential for small projects.
Separate a central estimate from a conservative financing or planning case. Ask what probability statement means, over what period it applies and whether uncertainty concerns resource measurement, future weather or equipment performance. Compare actual operating years with their own weather conditions before concluding that an estimate was either met or missed.
Include delivery and system needs
Find the proposed point of interconnection, connection status and responsibility for upgrades. Ask how much output may be curtailed because of transmission constraints, market conditions or operating restrictions, and who bears that lost revenue. A signed equipment order and a secured grid connection represent different project milestones.
Compare annual energy alongside hourly production and the local demand pattern. Storage, transmission and other generation can change the system contribution, each with its own costs and constraints. Use the grid-failure guide to distinguish adequacy questions from transmission or distribution faults.
For a small wind installation, first define the purpose: serving on-site demand, exporting power or supplying an isolated load. DOE’s wind overview explains that distributed wind is defined by its application. A utility-scale average cannot substitute for an assessment of a specific property, tower, approvals and tariff.
Evaluate impacts and lifetime obligations
The U.S. Fish and Wildlife Service land-based wind guidelines provide a tiered approach to wildlife assessment. Seek the actual site surveys, avoidance measures, post-construction monitoring and response commitments. Confirm applicable permits with the responsible authorities; a general guideline is one input to that process.
Request site-specific sound and shadow-flicker assessments, access-road and construction plans, complaint procedures and the operating restrictions included in the energy model. Check who maintains the equipment and how decommissioning, restoration and financial security are assigned.
Compare costs on the same basis: turbines, construction, connection, financing, lease payments, maintenance, major component replacement and end-of-life obligations. A levelized generation-cost estimate and a household retail tariff cover different services. A useful review leaves each unresolved assumption attached to an accountable document or party.