UK Energy Market Report - 4 September 2026

Day-ahead peak power settles below baseload as solar and wind flatten the daytime curve, while the whole gas board gives back around 4p

Something unusual happened on the UK power market on Thursday 3 September. Day-ahead peak settled at £66.00/MWh against a day-ahead baseload of £94.88/MWh, putting the 7am to 7pm window £28.88 below the round-the-clock price.

Peak is normally the expensive part of the day. When it settles at a discount that large, solar and wind are covering the daytime block and the expensive plant is only needed after dark.

Gas told a quieter version of the same story. Every NBP contract on the board fell, with the near curve giving back roughly 4p/therm and day-ahead down 5.10p to 175.50p.

Gas Market

NBP day-ahead settled at 175.50 p/therm on 3 September, down 5.10p or 2.82% on the day.

The curve moved with it, and moved as one. Oct-26 settled at 177.99p, down 4.16p, Q4-26 at 180.52p, down 4.22p, and Winter-26 at 178.45p, down 4.02p. Summer-27 fell 1.95p to 119.56p.

This morning the front has softened a little further. At 09:20 the indicative day-ahead was 174.79p and Winter-26 was marked at 177.46p.

The system explains most of the prompt weakness. Britain opened around 20 mcm/day long, against 6 mcm/day long the previous morning. On a like-for-like 07:00 comparison, system demand fell 12.92 mcm/day to 79.53, UKCS production edged up 0.80 to 80.00, and linepack built 14.44 to 344.10 mcm.

Norwegian supply is the counterweight, and it changed shape overnight rather than improving. The unplanned Kollsnes maintenance that has run through this week concluded and those flows returned, but Troll then entered unplanned corrective maintenance, taking 6.7 mcm/day out. Scheduled work started at several other facilities the same day.

The net effect is that flows to the UK are down around 5 mcm/day, with Langeled at 11.00 mcm/day against 15.00 the previous morning. Gassco recorded total exit nominations of 274.9 mcm/day.

Britain is once again the cheapest gas hub in Europe, and the discount is widening. NBP settled at 175.50p against TTF at 179.55p, PEG at 179.47p, Spain’s PVB at 185.52p and Italy’s PSV at 191.42p. Three sessions ago Spain was briefly cheaper than Britain; NBP now sits 4.05p under TTF and 10.02p under PVB.

The most useful number on the gas board is not on the front. Winter-27 settled at 115.87p, which is 62.58p below Winter-26. The market is pricing this as a 2026/27 problem, not a permanent one.

One caveat on the far curve. This morning’s index marks Summer-28 at 84.99p against a settlement of 77.86p, a jump of 7.13p. That is the identical print the same contract carried yesterday, and it appeared twice in a row in August too. Those contracts barely trade, and a repeated mark is a stale quote rather than a 9% move.

Demand is set to firm from here. Gas-for-power burn is forecast up 11 mcm/day day-on-day as wind eases into the weekend, which is the mechanism that will pull the system back from its 20 mcm/day long position.

Electricity Market

UK day-ahead baseload settled at £94.88/MWh, down £19.26 or 16.87% from Wednesday’s £114.14. Day-ahead peak settled at £66.00/MWh, down £24.80 or 27.31%.

The imbalance market shows how far it went intraday. On 3 September the minimum system sell price was minus £16.10/MWh at 12:18, so at the middle of the day generators were paying to stay on the system. The maximum system buy price that day was £214.90/MWh at 16:48, once solar came off.

Worth owning a miss here. Yesterday’s report published 3 September’s part-day imbalance figures as £183.95 maximum and £39.62 minimum, stamped shortly after 08:00. The settled day came in at £214.90 and minus £16.10, out by £30.95 on the ceiling and £55.72 on the floor. That floor miss is the largest this report has recorded, and it happened because the 09:00 print cannot see a midday that goes negative.

The forward curve barely reacted. Oct-26 baseload settled at £140.07/MWh, down only £1.49, Q4-26 at £145.92, down £1.66, and Winter-26 at £145.05, down £2.23. Summer-27 slipped £1.24 to £98.32.

A 17% fall on the prompt against a 1.5% fall on Winter-26 is the shape that matters. Nothing about the winter risk changed on Thursday; the weather simply took care of one day.

Nuclear availability is the reason the winter contract will not follow the prompt down. Four units go fully offline for planned outages between today and 7 September: Heysham 2-8 at 660 MW from today for a scheduled 80 days, Torness 1 at 640 MW from 6 September, and Heysham 1-1 at 610 MW and Hartlepool 2 at 620 MW both from 7 September.

That is 2,530 MW of firm baseload leaving the system inside four days, on top of the unplanned reduction at Heysham 1-2. Forecast wind and solar output also eases from tomorrow before recovering into next week, so the conditions that produced Thursday’s negative midday are not a standing feature.

Coal contributed nothing across the last fifteen days, and renewables were the largest single block in the generation mix over that window, ahead of CCGT and well ahead of nuclear. That is the structural reason midday prices can collapse in September in a way they could not five years ago.

On the morning index, a correction in this report’s favour and one worth stating plainly. Yesterday’s 09:19 marks put gas day-ahead at 176.80p against an actual settlement of 175.50p, and power day-ahead at £93.00 against £94.88. Winter-26 was marked within 0.18p on gas and £0.45 on power. That is a good morning for the index after misses of £20.70 and £35.50 on the power prompt in August, but three close prints do not make it reliable, and we will keep quoting it as an indication with its timestamp rather than a forecast.

Oil, Carbon and Global Commodities

The commodity complex was close to flat, which is itself notable on a day the UK curve moved.

Brent settled at $95.52/barrel, essentially unchanged at 11 cents lower. This morning crude is still on course for its strongest weekly gain since mid-July, on US-Iran tensions and the supply risk that carries.

Carbon eased on both sides of the Channel. EUA Dec-26 settled at €83.53/tonne and UK ETS Dec-26 at £59.49/tonne. At Thursday’s rate of 1.1620, the EUA is worth roughly £71.88, so UK allowances remain about £12.39 or 17% cheaper than European ones.

The LNG signal is the one to watch. JKM eased to $25.17/MMBtu but its premium over NBP spot widened to $1.44/MMBtu, from $1.17 two sessions ago. Asia is still bidding harder than northwest Europe for the same cargo.

Storage and Supply Outlook

European storage remains the structural problem behind the winter curve. EU stocks are roughly 65.6% full, well below where they sat at this point in recent years.

The country picture is uneven. Italy is 82% full and Spain 73%, France 69%, Germany 52% and Britain 48%. The Netherlands and Belgium sit at 46% and 53%.

Britain’s position is worse than the 48% headline implies, because Rough is at zero. So is Humbly Grove. The working stock is concentrated in HolFord at 75%, Stublach at 73%, Holehouse Farm at 70% and the LNG tanks at South Hook, 68%.

Ten cargoes are scheduled into northwest European terminals between today and Sunday, roughly 1,005 mcm of regas volume, and six of the ten are US-origin. UK sendout is expected to hold near 8 mcm/day across the weekend, split between Isle of Grain at 3.20 and South Hook at 4.90.

Britain is also still a net exporter to the continent through BBL, at 13.53 mcm/day into the Netherlands, with the Belgian interconnector idle. A country holding 48% storage exporting gas in early September is a fair summary of how tight the winter looks relative to the present.

That is a comfortable near-term supply picture sitting on top of an uncomfortable storage one, which is exactly why the prompt can fall 17% while Winter-26 moves 1.5%.

What This Means for Your Business

Thursday was a good day to be buying power and a poor day to read much into it. A negative midday system price and a peak-below-baseload settlement are weather events, not a change in the winter position.

The number to plan around is Winter-26 at £145.05/MWh and 178.45 p/therm, both of which moved by less than 2% on a day the prompt moved by 17%. If your renewal sits inside the 2026/27 winter, the curve has not offered you anything this week.

The number that should shape a longer decision is Winter-27, at 115.87 p/therm for gas and £99.35/MWh for power. Gas one winter further out is 62.58p cheaper and power is £45.70 cheaper. A contract that reaches past next winter buys into a materially different curve, which is the case for looking beyond a straight twelve-month renewal.

For businesses with significant daytime load, Thursday is also a reminder that the shape of your consumption is now worth real money. Peak settling below baseload is not a one-off any more, and a properly structured electricity contract should let you benefit from it rather than pay a flat blended rate through it.

Buyers exposed to the gas curve face the harder call, because the front is soft and the winter is not. Splitting a requirement into tranches rather than fixing the whole volume on one morning is the standard answer, and our flexible procurement service exists to do exactly that.

If you want to know what these movements mean for your own contract dates and consumption profile, speak to one of our energy consultants today.

Previous report: UK Energy Market Report – 3 September 2026