Future Energy Scenarios 2022 and its significant flaws

Future Energy Systems 2022 (FES 2022) was published in July 2022 by National Grid ESO (GB's electrcity system operator) and predicates various scenarios leading to Net Zero emissions by 2050. The data below is taken from Table ES1 using the “Leading the Way” scenario.

The table details changes in the electricity capacity year on year up to 2050 with the percentage make up of each major component. (Note: this is transmission (metered) capacity.)

 

At present the grid relies mainly on gas for its supply, closely followed by wind, then interconnectors and nuclear. However, by 2050 all fossil fuels will have been removed and wind generation dominates supply, with capacity being almost 5x that in 2022 and 66% of total capacity. It is backed up by significant increases in interconnector capacity plus storage. Note: storage is shown in italics as it is not generation and is reliant on other sources to charge the installed capacity.

It can also be seen that the total capacity in 2050 is 2.7x that in 2022. This is because peak demand is predicted to increase from 47424 MW in 2022 to 104001 MW in 2050, a factor of 2.2.

In summary, by 2050 the National Grid will be reliant principally on wind to meet demand with imports and storage being needed when wind is not directly available. It should be noted again that stored energy will have to be generated and this will principally be by wind.

So is this a reasonable and realistic scenario? It is reliant on enough wind being available to meet demand as it fluctuates throughout the day and to charge storage devices when wind generation exceeds demand.

Note: this analysis covers the major power sources only where a comparison can be made using data from 2022.

Average and Minimum Contribution to Demand by Wind

The table below shows the average contribution made by wind to demand month by month in 2020 and 2022 compared with the capacities given in “Leading the Way” in Table ES1 of FES 2022. (Note:2021 data taken from FES 2021).

 

As can be seen, despite a 33% increase in wind capacity and hence an expected 33% increase in generation, the average contribution has only risen marginally from 22.6% in 2020 to 24.4% in 2022. Without the high winds experienced in February and October, when the UK experienced some storms, the average percentage month by month contribution may well have been less than in 2020. (Wind generated 61686GWh in 2022 compared with 54701GWh in 2020.)

But averages do not give a true picture. If we are to become reliant on wind as the major contributor to the National Grid, we must also look at the times when wind does not make any significant contribution.

 

This is a mixed picture, with February being an anomaly, but how long do these periods of low contribution to demand last? This is best analysed by looking at wind lulls – periods when wind contribution is lower than a certain level.

Wind Lulls Analysis

Capacity has increased by 33% and therefore a significant reduction in wind lulls, taken as when wind contributes less than 5% of demand, may be expected. The table below details wind lulls in 2022 and a comparison with 2020 is given at the foot of the table.

 

Despite the significant increase in installed wind turbine metered capacity in the UK between 2020 and 2022 as detailed earlier, in every aspect of the analysis there is little difference in the wind lull pattern in 2022 compared with 2020.

Without the high winds of February and October, the overall figures could have been much worse.

The table confirms that low wind speeds are not unusual, in fact they are frequent and often extended. Assuming weather patterns remain the same in future years, it can also be assumed that wind lulls will not significantly decrease as the capacity of operational wind turbines is increased.

The extent of wind lulls can be shown graphically and it can clearly be seen from the graphs below, for summer and winter, that wind lulls are very frequent and often long lasting, so dispelling the myths that wind always blows somewhere and periods of widespread low wind are infrequent.

8 lulls totalling 93.5 hours – longest was 40 hours

7 lulls totalling 46 hours – longest was 39 hours

How does the National Grid cater for Wind Lulls with changing demand?

As can be seen from the above graphs, it is mainly gas (CCGT) which caters for fluctuations in demand. Nuclear provides a steady base contribution.

In June, when demand is relatively low at a peak of about 32000MW, gas was contributing around 18000MW, over 55%, during the three long (over 10 hours each) wind lulls.

In December, when peak demand it is relatively high at about 45000MW, gas is again the main contributor at around 24000MW, over 50%, during the prolonged wind lull of over 1½ days.

What will happen when we reach 2030 and 2050?

This is best illustrated by looking at a shorter time period, for example the first two weeks in December.

 

Only home generated supplies are shown, with imports omitted plus minor fuel sources for clarity. Although it may be noted that coal was used for generation continuously throughout December 2022.

Using the figures for increased demand, including electrolysis, and significantly increased wind capacity, in 2030 and 2050, as detailed in Table ES1 of FES 2022 earlier and assuming the same weather patterns, the contribution from wind would be as shown below over the first two weeks of December 2030 and 2050.

 

It can be seen that there is a massive shortfall in supply over most of the period. The average shortfall is 13697MW and the maximum 36555MW at 16.30 on 12 December. In terms of GWh over the period, this shortfall totals 4602 GWh.

 

In 2050, the situation is significantly worse. The average shortfall is 43960MW and the maximum 86695MW again at 16.30 on 12 December. There is only a 2½ hour period around 0400 on 4 December when supply exceeds demand. In terms of GWh over the period, this shortfall totals 14471 GWh.

Although interconnector capacity is forecast to increase to 19450MW by 2030, and 27350MW by 2050, these cannot meet peak demand even if imports are at 100% of capacity.

Storage capacity is forecast to increase from 26GWh in 2022 to 160GWh in 2050 (Leading the Way scenario). Using the data at the start of this note shows that this storage would be used up within 5 hours at 100% or 10 hours at 50% and would also be totally inadequate to cater for such fluctuations in supply caused through reliance on such an unpredictable source of supply as wind.

Conclusions

In 2022 gas (CCGT) provided the flexibility to meet demand and was by far the biggest contributor to demand at 42%. Nuclear provided a steady contribution of 18%, interconnectors 16%, wind 24% and biomass 6% (all figures rounded.)

By 2030 FES 2022 predicts that gas (CCGT) capacity will have been reduced by a third and nuclear by a similar amount. Biomass will remain the same but interconnector capacity will have increased by three times.

By 2050 FES 2022 predicts that gas (CCGT) capacity will have been eliminated and that supply will be mainly by wind at 5x current capacity and interconnectors at 4x current capacity. There will have been a small increase in biomass generation and a small reduction in nuclear. Combined these will only represent 6% of capacity.

Although storage will have increased from 26GWh in 2022 to 160GWh in 2050, this is totally inadequate to cope with shortfalls in supply caused by lengthy wind lulls. Some estimates put the required storage capacity at 10,000GWh.

With the variation in wind generation predicted for 2050 based on real current data from the National Grid, and the reliance on wind as the major contributor to capacity, there will be frequent and protracted power outages as storage will be unable to cope with the deficiencies in supply over extended periods of time.

It is also debatable whether it is prudent to rely on imports as a major contributor as higher demand and a significant reduction in reliance of fossil fuels in Europe may mean that they may be unwilling/unable to export to the UK. Examples have already been seen in the past 12 months when France experienced issues with their nuclear plants and Norway a lack of hydro power due to limited rainfall.