- Wind speeds are from GFS forecasts and cover quite a wide area
- The realtime generation data from the balancing system isn't 100% precise and is averages over a 30-minute period
- Some wind farms are simply much more efficient, especially large offshore ones
- Individual turbines might be down for maintenance and/or not running efficiently
- Localised issues like wake effects and turbulence
I'm not an expert in all this though so take it with a pinch of salt – I'm just very interested in it all and love making visualisations about it.
All that said, one of the intents behind creating the map is to highlight exactly this sort of stuff and to spark a discussion around why it might be.
Also another reason - a generation site may be curtailed, meaning that its output is restricted due to grid capacity limitations, and allowing it to export more energy onto the local power network may exceed safe operating parameters for the lines connecting the generation site to the grid.
Therefore in high wind, you would expect that in areas of dense generation, especially those with limited capacity interconnects to the rest of the grid, curtailment may be seen.
I could see this being the case for regional balancing, but presumably a 1GW generation site has a 1GW-capable link to the grid, otherwise that seems like overbuilt capacity?
(nb of course you might overprovision it to some degree on the presumption that, say, only 70% of your generation is usable at any one time; I more mean the numbers like say 16%.)
What's going on with Seagreen? It's got a forecast of 4MW, and a listed output of 545MW at roughly half capacity, in what seems like pretty light winds.
This is something I need to look into further but it's currently under construction and being tested. I'm pretty sure they have issued "down for maintenance" notices that I need to take into consideration and supersede any reported generation.
- Wind speeds are from GFS forecasts and cover quite a wide area - The realtime generation data from the balancing system isn't 100% precise and is averages over a 30-minute period - Some wind farms are simply much more efficient, especially large offshore ones - Individual turbines might be down for maintenance and/or not running efficiently - Localised issues like wake effects and turbulence
I'm not an expert in all this though so take it with a pinch of salt – I'm just very interested in it all and love making visualisations about it.
All that said, one of the intents behind creating the map is to highlight exactly this sort of stuff and to spark a discussion around why it might be.