UK offshore wind capacity factors

Posted by – 2021/03/01

Here are the average capacity factors for offshore wind farms in UK waters, newly updated to include data to the end of 2020 (though there are still some figures to come through for the last couple of months of last year, for the smaller windfarms). There are 38 operational windfarms presented here, and three closed demonstration sites.

2020 set a new record for the highest annual average capacity factor for a UK offshore windfarm: Hywind Scotland achieved 57.1% in the twelve months to March 2020. This floating windfarm, has behaved differently to any windfarm we’ve seen before, and that’s best portrayed in its load duration curve.

The load-duration curves at the bottom of this page show the differences in distribution of outputs: click on the individual farm names in the legend, to toggle the display of individual curves.

You might be interested in comparing these with the capacity factors and load-duration curves for Belgium, Denmark and Germany.

All numbers are to the end of 2020. Analysis by Raw data from Ofgem and Elexon
elec. gen.
Power per
unit area
spanned (W/m2)
Rolling annual
capacity factors
(click to enlarge)
Aberdeen EOWDC 38.2% 37.5% 2.5937681.7Aberdeen EOWDC
Barrow 32.3% 35.7% 14.3904,0283.2Barrow
Beatrice 46.3% 47.4% 1.65883,8942.1Beatrice
Burbo Bank 37.0% 34.0% 13.2903,5443.1Burbo Bank
Burbo Bank 2 45.0% 41.1% 3.82543,4442.6Burbo Bank 2
Dudgeon 49.6% 48.1% 3.34025,5283.5Dudgeon
East Anglia ONE 48.6% 52.3% 0.47141,4492.3East Anglia ONE
Galloper 51.0% 47.0% 2.73533,9971.5Galloper
Greater Gabbard 43.6% 41.0% 7.450413,5401.4Greater Gabbard
Gunfleet Sands 41.7% 37.0% 10.51735,9484.0Gunfleet Sands
Gwynt-y-Mor 37.6% 35.0% 5.55769,8623.0Gwynt-y-Mor
Hornsea One 48.4% 48.3% 1.01,2185,1911.4Hornsea One
Humber Gateway 46.5% 43.7% 5.62194,7023.5Humber Gateway
Hywind Scotland 53.1% 53.6% 3.2304581.1Hywind Scotland
Lincs 46.1% 42.5% 7.32707,3732.8Lincs
London Array 46.7% 40.2% 7.763017,3432.1London Array
Ormonde 39.7% 37.9% 8.91504,4325.7Ormonde
Race Bank 47.4% 43.5% 2.95736,3814.0Race Bank
Rampion 44.6% 34.7% 2.74003,3461.9Rampion
Robin Rigg 41.0% 35.7% 10.31745,6543.5Robin Rigg
Sheringham Shoal 41.8% 40.2% 7.33178,2043.6Sheringham Shoal
Thanet 39.0% 33.5% 10.33009,0922.9Thanet
Walney phase 1 41.2% 40.3% 9.51846,1812.6Walney phase 1
Walney phase 2 47.7% 45.9% 8.51846,3161.9Walney phase 2
Walney 3 & 4 49.8% 49.1% 2.36596,7812.2Walney 3 & 4
Westermost Rough 51.6% 47.8% 5.62104,9512.9Westermost Rough
West of Duddon Sands 47.7% 46.0% 6.23899,7082.7West of Duddon Sands
Beatrice Demo (closed) 14.6% 18.9% 8.310123Beatrice Demo (closed)
Blyth Demo (closed) 18.0% 9.2% 12.8439Blyth Demo (closed)
Blyth Demo Array 2 45.3% 44.0% 2.542405Blyth Demo Array 2
Fife Demo 25.5% 13.3% 6.8759Fife Demo
Gunfleet Sands Demo 34.0% 31.3% 7.3122521.5Gunfleet Sands Demo
Inner Dowsing 34.6% 35.0% 11.8973,5313.9Inner Dowsing
Kentish Flats 26.7% 30.5% 15.1903,6302.8Kentish Flats
Kentish Flats Extension 37.0% 40.7% 5.1508982.4Kentish Flats Extension
Kincardine demo (closed) 43.6% 1.9213Kincardine demo (closed)
Lynn 35.2% 35.1% 11.8973,5344.3Lynn
North Hoyle 36.0% 32.5% 16.5602,8252.0North Hoyle
Rhyl Flats 38.4% 34.2% 11.1902,9863.2Rhyl Flats
Scroby Sands 35.9% 31.3% 16.1602,6514.5Scroby Sands
Teesside 39.5% 36.4% 5.8621,1385.2Teesside

Load duration curves

I’ve constructed for each of the offshore windfarms for which there is half-hourly metered data. Use the pause and play buttons to stop and start the sequential display of curves. Click on the windfarm name in the legend to toggle the display of that farm’s curve.

Note that for each individual windfarm, its curve is based on data starting from either January 2009, or from the date that the windfarm was fully commissioned, whichever is more recent. The curve for all windfarms is for the last five years.

Capacity factor calculation method

Just as with the Danish offshore windfarm capacity factors, the capacity factors are calculated by calculating, for each wind farm, the number of hours since it was commissioned. This is then multiplied by its capacity, to give the number of peak-MW-hours. This is divided into the total energy generated by that wind farm, to give its capacity factor. The input energy data is from Elexon, and goes back to 2009; and from Ofgem, which goes back to 2000. There are some UK offshore windfarms for which Elexon does not have metered data: for those, I’ve used the REGO data from Ofgem.

To cite this page: by Andrew ZP Smith, ORCID 0000-0002-8215-4526


Please cite this page as:

Andrew ZP Smith, ORCID: 0000-0003-3289-2237; "UK offshore wind capacity factors". Retrieved from on 2021-11-24 20:07 GMT