22 research outputs found
An intercomparison of mesoscale models at simple sites for wind energy applications
Understanding uncertainties in wind resource assessment associated with the
use of the output from numerical weather prediction (NWP) models is important
for wind energy applications. A better understanding of the sources of error
reduces risk and lowers costs. Here, an intercomparison of the output from 25
NWP models is presented for three sites in northern Europe characterized by
simple terrain. The models are evaluated using a number of statistical
properties relevant to wind energy and verified with observations. On average
the models have small wind speed biases offshore and aloft (< 4 %)
and larger biases closer to the surface over land (> 7 %). A similar
pattern is detected for the inter-model spread. Strongly stable and strongly
unstable atmospheric stability conditions are associated with larger wind
speed errors. Strong indications are found that using a grid spacing larger
than 3 km decreases the accuracy of the models, but we found no evidence
that using a grid spacing smaller than 3 km is necessary for these simple
sites. Applying the models to a simple wind energy offshore wind farm
highlights the importance of capturing the correct distributions of wind
speed and direction