Articles | Volume 10, issue 9
https://doi.org/10.5194/wes-10-2025-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wes-10-2025-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Sep 2025
Research article |
| 15 Sep 2025
| 15 Sep 2025
Upwind vs. downwind: loads and acoustics of a 1.5 MW wind turbine
Pietro Bortolotti
CORRESPONDING AUTHOR
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Lee Jay Fingersh
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Nicholas Hamilton
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Arlinda Huskey
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Chris Ivanov
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Mark Iverson
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Jonathan Keller
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Scott Lambert
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Jason Roadman
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Derek Slaughter
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Syhoune Thao
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
Consuelo Wells
National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401, USA
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Ernesto Camarena, Evan Anderson, Josh Paquette, Pietro Bortolotti, Roland Feil, and Nick Johnson
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Pietro Bortolotti, Nick Johnson, Nikhar J. Abbas, Evan Anderson, Ernesto Camarena, and Joshua Paquette
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Short summary
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Luis A. Martínez-Tossas, Jennifer King, Eliot Quon, Christopher J. Bay, Rafael Mudafort, Nicholas Hamilton, Michael F. Howland, and Paul A. Fleming
Wind Energ. Sci., 6, 555–570, https://doi.org/10.5194/wes-6-555-2021, https://doi.org/10.5194/wes-6-555-2021, 2021
Short summary
Short summary
In this paper a three-dimensional steady-state solver for flow through a wind farm is developed and validated. The computational cost of the solver is on the order of seconds for large wind farms. The model is validated using high-fidelity simulations and SCADA.
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Short summary
This study compares a wind turbine with blades behind the tower (downwind) to the traditional upwind design. Testing a 1.5 MW turbine at the National Renewable Energy Laboratory's Flatirons Campus, we measured performance, loads, and noise. Numerical models matched well with observations. The downwind setup showed higher fatigue loads and sound variations but also an unexpected power improvement. Downwind rotors might be a valid alternative for future floating offshore wind applications.
This study compares a wind turbine with blades behind the tower (downwind) to the traditional...
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