Estimating air density using observations and re-analysis outputs for wind energy purposes

Rogier Ralph Floors*, Morten Nielsen

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

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Abstract

A method to estimate air density as a function of elevation for wind energy resource assessments is presented. The current practice of using nearby measurements of pressure and temperature is compared with a method that uses re-analysis data. It is found that using re-analysis data to estimate air density gives similar or smaller mean absolute errors compared to using measurements that were on average located 40 km away. A method to interpolate power curves that are valid for different air densities is presented. The new model is implemented in the industry-standard model for wind resource assessment and compared with the current version of that model and shown to lead to more accurate assessment of the air density at different elevations.
Original languageEnglish
Article number2038
JournalEnergies
Volume12
Issue number11
Number of pages12
ISSN1996-1073
DOIs
Publication statusPublished - 2019

Keywords

  • Air density
  • Wind energy
  • Power curves
  • WAsP
  • ERA5
  • CFSR

Cite this

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title = "Estimating air density using observations and re-analysis outputs for wind energy purposes",
abstract = "A method to estimate air density as a function of elevation for wind energy resource assessments is presented. The current practice of using nearby measurements of pressure and temperature is compared with a method that uses re-analysis data. It is found that using re-analysis data to estimate air density gives similar or smaller mean absolute errors compared to using measurements that were on average located 40 km away. A method to interpolate power curves that are valid for different air densities is presented. The new model is implemented in the industry-standard model for wind resource assessment and compared with the current version of that model and shown to lead to more accurate assessment of the air density at different elevations.",
keywords = "Air density, Wind energy, Power curves, WAsP, ERA5, CFSR",
author = "Floors, {Rogier Ralph} and Morten Nielsen",
year = "2019",
doi = "10.3390/en12112038",
language = "English",
volume = "12",
journal = "Energies",
issn = "1996-1073",
publisher = "M D P I AG",
number = "11",

}

Estimating air density using observations and re-analysis outputs for wind energy purposes. / Floors, Rogier Ralph; Nielsen, Morten.

In: Energies, Vol. 12, No. 11, 2038, 2019.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Estimating air density using observations and re-analysis outputs for wind energy purposes

AU - Floors, Rogier Ralph

AU - Nielsen, Morten

PY - 2019

Y1 - 2019

N2 - A method to estimate air density as a function of elevation for wind energy resource assessments is presented. The current practice of using nearby measurements of pressure and temperature is compared with a method that uses re-analysis data. It is found that using re-analysis data to estimate air density gives similar or smaller mean absolute errors compared to using measurements that were on average located 40 km away. A method to interpolate power curves that are valid for different air densities is presented. The new model is implemented in the industry-standard model for wind resource assessment and compared with the current version of that model and shown to lead to more accurate assessment of the air density at different elevations.

AB - A method to estimate air density as a function of elevation for wind energy resource assessments is presented. The current practice of using nearby measurements of pressure and temperature is compared with a method that uses re-analysis data. It is found that using re-analysis data to estimate air density gives similar or smaller mean absolute errors compared to using measurements that were on average located 40 km away. A method to interpolate power curves that are valid for different air densities is presented. The new model is implemented in the industry-standard model for wind resource assessment and compared with the current version of that model and shown to lead to more accurate assessment of the air density at different elevations.

KW - Air density

KW - Wind energy

KW - Power curves

KW - WAsP

KW - ERA5

KW - CFSR

U2 - 10.3390/en12112038

DO - 10.3390/en12112038

M3 - Journal article

VL - 12

JO - Energies

JF - Energies

SN - 1996-1073

IS - 11

M1 - 2038

ER -