Source
https://www.energy.gov/eere/wind/windexchange/small-wind-handbook — original source (opens in a new tab; the file is not redistributed)
US DOE WINDExchange — Small Wind Guidebook
The m/s->capacity-factor method for small wind (RT_290)
Summary
The US DOE consumer/technical guidebook for small wind systems. It supplies the standard energy-estimation method the model uses to turn a sampled site wind speed into a capacity factor: a quick annual-energy formula, the wind-distribution assumption that underlies manufacturer/certified AEO curves, and the underlying wind-power equation.
Key claims
- claim: "Quick annual-energy estimate: 'AEO = 0.01328 D2 V3', where AEO = annual energy output (kWh/year), D = rotor diameter (feet), and V = annual average wind speed (mph)."
source_location: "Small Wind Guidebook — energy-estimation section (confirmed in raw page HTML via curl+grep)"
- claim: "Manufacturer/certified energy curves assume a standard wind-speed distribution: an energy curve is 'a diagram showing the annual energy production at different average wind speeds, typically assuming a Rayleigh wind distribution (with a Weibull shape factor of 2.0)'. This is what licenses applying a datasheet AEO-vs-mean-speed curve (or a certified 5 m/s Rated Annual Energy) to a site known only by its mean wind speed."
source_location: "Small Wind Guidebook — glossary, 'Energy curve' (confirmed in raw HTML)"
- claim: "Wind power equation: 'Power = Cp 1/2 rho A V3', where Cp = power coefficient (0.25-0.45; Betz theoretical max 0.59), rho = air density (kg/m3), A = rotor swept area (m2), V = wind speed (m/s). Establishes output proportional to V3 (so hub-height wind speed dominates) and to swept area."
source_location: "Small Wind Guidebook — how wind turbines work / swept area section (confirmed in raw HTML)"Neobiome Intelligence relevance
The method half of RT_290. Two conversion paths for the sampler’s site mean wind speed (~50 m) -> capacity factor:
- Preferred — power curve: integrate a turbine’s power curve against a Rayleigh distribution (Weibull k=2.0) at the site mean speed to get annual energy, then CF = AEO ÷ (rated kW × 8,760). Reference curves: NZ Thinair (DS_001) and certified Bergey Excel 15 (DS_002).
- Quick estimate — no curve: AEO = 0.01328·D²·V³ (imperial), then CF = AEO ÷ (rated kW × 8,760).
The Rayleigh / Weibull-k=2.0 statement is what makes a datasheet or certified 5 m/s figure valid for an NZ site known only by its mean wind speed — and why the model must apply one consistent Rayleigh integration rather than trust each datasheet’s own AEO example (e.g. the Thinair worked example uses k=3). Enables the D25 “#9” wind site-override (site wind_cf replacing the regional lookup). NZ boundary: the method is universal; only the wind-speed input is NZ-specific (NIWA / Global Wind Atlas per CR_029).
Research targets
Documents to retrieve
- None new.
Research gaps
- Covered by RT_140 (NZ regional wind-speed layer at hub height to drive this method).
Notes
Web page captured direct via curl (energy.gov), no AI-retrieval provenance; the three method strings were grep-confirmed in the raw HTML (0.01328 D² V³; Rayleigh / Weibull shape factor 2.0; Cp 1/2 ρ A V³). data_quality high (US-govt guidebook).
Connections
Links to
Referenced by
Sources (3): CR_054 · DS_001 · DS_002
EDT domains (1): D01: Renewable Energy & Storage Systems
Technologies (1): community-scale)