Hornsea 2 has a capacity of 1,320MW, and was the largest offshore wind farm in the world on completion.
The Orsted website tells us that it is "providing enough green electricity to power 1.4 million homes" in one place, but that it "will help power over 1.4 million UK homes with low-cost renewable energy" elsewhere. The chart on this page should help to assess those statements.
According to the Orsted website it became fully operational on 31 August 2022.
Let's take a look at its progress, with updates from time to time.
Hornsea 2 generation
This chart shows daily energy generated by Hornsea 2.
(For a more accurate assessment of its ability to supply homes consistently we should look at a more "real time" plot of energy generated, as even summing over a day smooths and hides the variability of wind. But for the purposes of seeing how it's performing the daily totals are a good starting point.)
The green horizontal line shows the energy that would be generated if the wind farm were working at a 50% capacity factor.
The red horizontal line shows the average electricity requirement of 1.4 million homes. This is based on a current Ofgem figure of 3,100kWh of electricity per year per UK household. This is set at 11.9GWh.
A 1.32GW wind farm working at name plate capacity would produce 31.68GWh per day, which explains the limit on the vertical scale.
Hornsea 2 so far
From 1 Sep 2022 to 30 Apr 2023 it was meeting Orsted's claim (on average over the day) for just over 62% of days.
So, for almost 38% of days it was not achieving Orsted's claim, even on average over a day.
On over a third of days, where will the power for those 1.4 million homes come from?
But what is most worrying is the number of days on which Hornsea 2 was generating very little electricity - if any.
On several days Hornsea 2 has taken more power from the grid than it put in. On two days it generated no power at all.