Another UK wind record was broken today. For the first time ever, total output of the major wind farms reached just over 6 gigawatts in the early afternoon. This was about 14% of the country’s total requirement for electricity, much less than it would have been if the storm had passed over the UK during the night. Nevertheless, today’s strong NW winds provided a fascinating little case history for us to look at. The flags on the flagpoles weren’t even fluttering in the daytime yesterday. Total output from wind turbines was little more than 5% of today’s figure. Wind speeds then strengthened consistently until early afternoon today. As expected, wind displaced gas in the electricity generation mix. The high level of wind output even resulted in small net exports to the rest of Europe.

Here’s what the pattern of supply looked like at 14.30 on the two adjacent days

Total electricity output at 14.30

Yesterday	44.6 gigawatts
Today	44.3 gigawatts	Down 2.3 gigawatts

The UK wind turbines that are not connected to the trunk of the electricity grid aren’t recorded in the records of electricity generation. Instead they reduce the total amount of power needed from the big generators. Friday tends to have a lower electricity demand than Thursdays but today’s high wind speeds are probably responsible for almost all of the difference between yesterday and today.

Today, the large wind farms were generating 5.7 gigawatts more than yesterday at the same time.

Wind output at 14.30

Yesterday	0.4 gigawatts
Today	6.1 gigawatts	Up 5.7 gigawatts

Taken together, high winds today reduced the need for power by about 8 gigawatts. Unsurprisingly, gas output was down almost exactly this amount. Coal power was virtually unchanged.

Output from gas fired power stations at 14.30

Yesterday	19.5 gigawatts
Today	11.2 gigawatts	Down 8.3 gigawatts

And, it’s worth pointing out there were no incidences of the use of oil-fired or open cycle power stations during this 24 hour period.

When the wind blows, fossil fuel power stations simply work less. Wouldn't it be wonderful if the wind power sceptics took a look at the data rather than continuing to assert that fossil fuel power stations work as back-up even when the wind is at its strongest?