Small Wind Feasibility Calculator

Small wind turbines have a well-earned reputation for disappointing paybacks compared to solar, and this calculator's built-in capacity factor formula makes that risk visible rather than hiding it. It estimates capacity factor from average wind speed using a simple linear rule — (wind speed − 3) × 0.05, clamped between 5% and 35% — which is a rough heuristic, not a physics-based power curve; real turbines have manufacturer-specific power curves that respond very differently to wind speed distribution, not just the mean. That capacity factor is multiplied by rated power and the 8,760 hours in a year to estimate annual kWh production, which is then valued at your electricity rate and reduced by annual maintenance cost to get net annual savings.

Total installed cost (turbine plus installation) is discounted by any incentive or rebate percentage you enter, and simple payback is that discounted cost divided by net annual savings — capped at 99 years if savings are zero or negative, a sentinel value flagging an infeasible system rather than a real multi-generation payback. Twenty-year ROI and levelized cost of energy (LCOE) both assume a flat 20-year system life with no degradation, no financing costs, no future maintenance escalation, and no changes to electricity rates over time. Because residential wind performance is extremely site-sensitive — a location with obstructed or turbulent wind flow will underperform this estimate significantly — treat the output as a rough screening tool, and pair it with an actual site wind assessment before committing to a purchase.