But will offshore wind compliment wind energy? If the peaks in offshore wind occurred during the lows in onshore wind, then that would be very useful. This would result in a smoothing out of the intermittent profile of onshore wind we are so familiar with. We could call such a renewable energy source a "complimentary source".
An example of a strong complimentary source would be perhaps solar energy, where during hot calm conditions such as last summer, solar energy would begin to peak just as wind energy fizzles out. In this case, we could say that solar and wind are negatively correlated, which indicates that they are strong complimentary sources.
To establish whether offshore wind is a strong or weak complimentary source, we can once again look at the data from Denmark, which has about 8GW of offshore wind capacity installed. In 2017, Euan Mearns analysed three years worth of data for both offshore and onshore wind, and found that the two are well-correlated (R squared = 0.71 for hourly data, 1 is a perfect correlation). This means that offshore wind is a relatively weak complimentary source. When the wind is blowing on land, chances are it's also blowing out at sea (and vice versa).
 |
| Hourly onshore (red) and offshore (blue) wind generation with total generation scaled up to meet total demand, Denmark, 2014-2016 (from Euan Mearns). |
References: http://euanmearns.com/can-offshore-wind-be-integrated-with-the-grid/
