Weekly Energy Market Report - Week 37

Day-ahead power finished the week 75p higher after travelling 162.63 a megawatt hour to get there, while gas ground steadily up to a multi-year high and the driver changed from wind to war.

Five settled sessions between 2 and 8 September left UK day-ahead baseload power at £154.45/MWh, against £153.70 the week before. A gain of 75 pence, or 0.49%.

Getting there took a fall to £72.76 and a rise back to £154.45. Adding up the five daily moves without regard to sign gives £162.63 of travel for a net £0.75. Trough to peak was 112%. Any buyer who looked at one screen last week saw a different market from any buyer who looked at another.

Gas did the opposite and did it quietly. NBP day-ahead added 11.25p to 189.25 p/therm, the highest settlement in this series, on 21.45p of total travel. More than half of the gas movement was direction; almost none of the power movement was.

What changed mid-week was the reason. The first three sessions were a weather story, with strong wind and solar collapsing the prompt. The last two were a supply and geopolitics story, with Norwegian outages, record Asian LNG pricing and an escalation between Iran and the United States that put Brent through $100.

Gas: a steady climb to a multi-year high

NBP day-ahead settled 180.60p, 175.50p, 179.00p, 182.00p and 189.25p across the week, closing 11.25p or 6.32% above the 178.00p it started from.

Only one session fell. Thursday 3 September took the prompt down 5.10p and the whole board with it, on strong renewable output and a long system. The other four rose, and the last of them rose 7.25p on its own, which is a third of the week’s net gain in one session.

The near curve tracked the prompt almost exactly. Oct-26 finished at 188.80p, up 10.51p, Q4-26 at 191.08p, up 10.31p, and Winter-26 at 189.40p, up 10.98p, a band of 5.7% to 6.2%. Summer-27 was the strongest of the group in percentage terms, up 9.66p or 8.25% to 126.68p.

The far end refused to join in. Summer-28 rose 1.52p to 78.72p and Winter-28 1.54p to 85.82p, under 2% each against 6% or more at the front, and both fell on the final session. The market is pricing a tight two winters and a normal one after that.

Britain lost and then regained the cheapest slot in Europe. NBP started the window 0.47p above Spain’s PVB, the first time it had not been cheapest in this run, and finished it 0.01p below. Against TTF the discount moved from 3.07p to 2.84p. Britain therefore spent the whole week within a few pence of the cheapest hub on the board while exporting gas through BBL to the Netherlands on every session.

Supply is why. Gassco nominations ran between 279.3 and 294.8 mcm/day through the week with unplanned outages at Kollsnes, Troll and Asgard, Dvalin maintenance running to 26 September, and Norwegian deliveries into Britain falling from 36 to 26 mcm/day between Monday and Tuesday.

The card below summarises where NBP contracts stood after the five settled sessions of this period.

Power: a round trip, and an inversion that opened and closed

Day-ahead baseload settled £114.14, £94.88, £72.76, £127.62 and £154.45 across the five sessions. Three falls of 26%, 17% and 23%, then a rise of 75% and a rise of 21%.

Day-ahead peak did the same thing further. It ran £90.80, £66.00, £44.84, £109.71 and £152.84, from £151.41 the week before, ending 1.43 higher after a low that was 70% below where it started.

The relationship between the two blocks is the week’s most useful number. Peak settled below baseload on all five sessions, as it had on 1 September, and the discount was £23.34, £28.88, £27.92, £17.91 and £1.61. It opened, widened across three sessions and shut inside two. September daytime solar and wind is what put peak under baseload; once the prompt repriced upward on fuel cost, the evening blocks took the weight back. If a decision for a daytime-weighted site was resting on that discount, it has all but gone.

The forwards, unlike the prompt, went one way. Oct-26 baseload added £9.52 to £147.24, Q4-26 £9.50 to £153.23, Winter-26 £9.27 to £152.91 and Q1-27 £9.05 to £152.59, all between 6.3% and 6.9%. The curve rose about 6.5% in a week in which the prompt finished flat, which tells you the market repriced winter risk rather than this week’s weather.

Thermal availability is behind that. Three nuclear units are fully offline on planned work, Heysham 2 reactor 8 at 660 MW, Torness 1 at 640 MW and Heysham 1 reactor 1 at 610 MW, with unplanned reductions of 240 MW at Hartlepool 2 and 195 MW at Heysham 1 reactor 2, the last of those booked for 186 days. A further 620 MW leaves at Hartlepool 2 on 14 September, the same day French nuclear staff hold a 24-hour strike.

The imbalance market was extraordinary throughout. The daily maximum system buy price ran £240.00, £233.50, £222.50, £213.77 and £202.90, while the daily minimum system sell price went as low as minus £84.88 on 5 September. A market that pays generators over £200 in the evening and charges them to generate at midday is a market with a shape problem, not a fuel problem, and it is the clearest argument for matching your purchasing approach to when you actually consume rather than to a single annual price.

Oil, carbon and LNG

Brent gained $3.27 or 3.46% across the week to $97.92/barrel and traded above $100 on the morning of 9 September, its first time there since 24 July. The move is entirely geopolitical: Houthi attacks on Saudi energy infrastructure early in the week, then Iranian missile strikes on a US base in Jordan, attacks on ten ships, the US destruction of five Iranian oil tankers, and a seized uncrewed submarine in the Strait of Hormuz.

Commodity	Settlement 8 Sep	Change on the week
Brent Crude M+1	$97.92/barrel	+3.46%
Coal API2 Cal-27	$134.30/tonne	+0.05%
EUA Carbon Dec-26	€85.42/tonne	+2.50%
UK ETS Dec-26	£60.92/tonne	+2.89%
JKM LNG M+1	$26.82/MMBtu	+6.98%

Asian LNG was the strongest mover after oil. JKM front month rose $1.75 or 6.98% to $26.82/MMBtu, its highest since early 2023, and it did almost all of that on the final session. Cargoes priced off JKM compete with European terminals, and Europe is the market with the storage gap, so a rising JKM is a direct cost to a UK gas buyer.

Coal went nowhere. API2 Cal-27 moved through $132.56 and $134.46 to finish at $134.30, seven cents above where it started. On a week when gas rose 6% and oil 3.5%, an unmoved coal contract is a reminder that the European thermal stack is set by gas.

Both carbon markets rose, and the UK scheme rose faster. EUA Dec-26 added €2.08 or 2.50% to €85.42/tonne while UK ETS Dec-26 added £1.71 or 2.89% to £60.92/tonne. At Tuesday’s rate of 1.1663 the UK contract is worth about €71.05, a discount of roughly €14.37 to the EUA. That gap narrowed slightly on the week, having widened through late August, and it is the number to watch if you report on both schemes or expect linkage. Anyone whose carbon reporting obligations are priced off either allowance saw costs rise faster than headline inflation for a second week.

Storage: everyone filled except Britain

European storage moved from around 65% to 66.9% full on 6 September, still about 12 percentage points below the same point last year, with daily net injections near 3.6 TWh.

The country detail is the story. Across the window France went from 69% to 73%, Belgium and the Netherlands from 46% and 53% to 49% and 57%, Germany from 52% to 54% and Italy from 82% to 83%. Spain held 73% throughout. Britain read 49%, then 48% mid-week, then 49% again. It ended the week exactly where it began.

That is now most of a month of no net progress. Britain first reached 49% on 27 August and has not moved off it since, while every other major European holder except Spain has added stock.

The site-level position explains why the headline understates the risk. Rough, the country’s largest seasonal facility, is at zero, and so is Humbly Grove. The working stock is in Stublach and HolFord at 75%, Holehouse Farm at 70%, Hornsea at 58% and Aldbrough at 51%. On the LNG side South Hook holds 63%, Dragon 33% and Isle of Grain 31%.

Ten cargoes are booked into northwest European terminals between 9 and 17 September, about 993 mcm, nine of them from the United States. Exactly one is going to a British terminal, 100 mcm into Milford Haven on 15 September. Britain is meanwhile still exporting to the continent through BBL at around 11.50 mcm/day.

The week ahead

Three dates matter. Wind and solar output is forecast to trough near 8,900 MWh on 10 September against a seasonal norm around 10,000, then run above norm to the 16th. Hartlepool 2 loses a further 620 MW to planned maintenance on 14 September. French nuclear staff strike for 24 hours the same day.

The UK temperature forecast is mild, at or above the seasonal mean every day to 16 September and reaching 17.3°C on the 14th, so demand is not the pressure. Price direction from here rests on the Strait of Hormuz and on Norwegian availability, neither of which a weather model will tell you about.

For a buyer, the practical read is that Winter-26 at 189.40 p/therm and £152.91/MWh has risen for three straight sessions to the top of its range, while Winter-27 sits 67.69p and £49.80 cheaper. That spread is the case for looking past a straight twelve-month renewal. Next week’s report picks up from the 8 September close.

For a view tailored to your consumption profile and renewal window, speak to one of our energy consultants today.

Previous report: Weekly Energy Market Report, Week 36

For the following week’s energy market analysis, read our Weekly Energy Market Report, Week 38.

For more recent analysis, read our Weekly Energy Market Report, Week 39.