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  • Featured in Physics
  • Open Access

Low-Level Cloud Radiative Forcing Enhances Wind-Farm Wake Recovery

Davide Selvatici* and Richard J. A. M. Stevens†

  • *Contact author: d.selvatici@utwente.nl
  • †Contact author: r.j.a.m.stevens@utwente.nl
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PRX Energy 5, 033014 – Published 2 September, 2026

DOI: https://doi.org/10.1103/86lm-1nr3

Abstract

Recent simulations and observations suggest that clouds interact with offshore wind farms, yet the physical mechanisms governing this interaction remain unclear. Here, we investigate these processes using large-eddy simulations of stratocumulus-topped boundary layers, systematically removing key forcings to isolate their physical effects. We consider three progressively simplified scenarios: (i) a fully developed marine stratocumulus boundary layer, (ii) a case without radiative forcing, which weakens both cloud-top longwave cooling and entrainment, and (iii) a clear-sky case in which both radiative forcing and liquid water are removed. The presence of cloud-top radiative cooling increases entrainment, leading to a less stable and deeper boundary layer that promotes vertical transport of momentum and energy toward the turbines. This leads to a faster wake recovery, with direct implications for the performance of neighboring wind farms. Overall, our results demonstrate that radiatively driven cloud-top entrainment is a key mechanism linking cloud dynamics to the performance of large wind farms and underscore the need for wind-energy models that explicitly represent interactions among wind farms, the atmosphere, and cloud processes.

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synopsis

The Effect of Clouds on Wind Farms

Published 2 September, 2026

Simulations suggest that clouds can reduce the length of a wind farm’s slow-air wake, potentially increasing power production of neighboring wind farms.

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Popular Summary

Offshore wind farms are often built in regions where low-level clouds are common. Until now, the influence of these clouds on wind-farm wake recovery has received little attention. Using detailed numerical simulations, the authors show that typical marine low-level clouds enhance atmospheric mixing. This effect is driven by radiative cooling at the cloud top, which strengthens vertical motions of air in the lower atmosphere where wind turbines operate. The resulting increase in turbulence allows wind-farm wakes to recover more quickly under cloudy conditions, improving the power production of downstream wind farms. The findings demonstrate that low-level clouds can play an essential role in offshore wind-farm performance and should be considered in future wind resource assessments and wind-farm design.

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PRX Energy 5, 033014– Published 2 September, 2026
  • Received 23 December 2025
  • Revised 9 May 2026
  • Accepted 24 June 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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