  We present a new high-resolution global renewable energy atlas ({REatlas})
that can be used to calculate customised hourly time series of wind and solar
PV power generation. In this paper, the atlas is applied to produce
32-year-long hourly model wind power time series for Denmark for each
historical and future year between 1980 and 2035. These are calibrated and
validated against real production data from the period 2000 to 2010. The high
number of years allows us to discuss how the characteristics of Danish wind
power generation varies between individual weather years. As an example, the
annual energy production is found to vary by $\pm10\%$ from the average.
Furthermore, we show how the production pattern change as small onshore
turbines are gradually replaced by large onshore and offshore turbines.
Finally, we compare our wind power time series for 2020 to corresponding data
from a handful of Danish energy system models. The aim is to illustrate how
current differences in model wind may result in significant differences in
technical and economical model predictions. These include up to $15\%$
differences in installed capacity and $40\%$ differences in system reserve
requirements.
